PC and Salesforce: Non printable characters populate cells when new headers added to .csv in Lightning Web Component

I inherited code for a Salesforce Lightning Web Component. In the JS, I added two string values to an array to append 2 additional column headers. When a PC user clicks on the LWC to download the .csv file, non printable characters populate the cells underneath the new headers and it looks like they are empty but they are not.
Sample .csv file, please see cell E2 and F2. Update Account Template (7).csv
LWC JS below:
import { LightningElement, track, api } from 'lwc';
import {ShowToastEvent} from 'lightning/platformShowToastEvent';
import csvFileRead from '@salesforce/apex/CsvFileReader.csvFileRead';
import updateFileTitle from '@salesforce/apex/CsvFileReader.updateFileTitle';
import cleanupFiles from '@salesforce/apex/CsvFileReader.cleanupFiles';
import workbook from '@salesforce/resourceUrl/sheetJsPro';
import { loadStyle, loadScript } from 'lightning/platformResourceLoader';
//import updateAccounts from '@salesforce/apex/CsvFileReader.updateAccounts';

 const columnsAccount = [{
    label: 'Account Id',
    fieldName: 'accId',
    type: 'text',
    sortable: false,
    wrapText: true
},
{
    label: 'Current Assignment Owner',
    fieldName: 'accCurrentAssignmentOwnerId',
    type: 'text',
    sortable: false,
    wrapText: true
},
{
    label: 'New Assignment Owner',
    fieldName: 'accNewAssignmentOwnerId',
    type: 'text',
    sortable: false,
    wrapText: true
},
{
    label: 'Failed Reason',
    fieldName: 'failedReason',
    type: 'text',
    sortable: false,
    wrapText: true
}];

/* CSV File Fields
AccountID, Current Assignment Owner Id, New Assignemnt owner Id, Assignment Reason, Deal Owner Id, Assigned To Id 
*/

export default class CSVFileReadLWC extends LightningElement {

    error;
    data;
    showMessage = false;  
    isLoading = false;
    columnsAccount = columnsAccount;
    recsToUpdate = false;
    numRecsToUpdate = 0;
    numFailedRecs = 0;

    // accepted parameters
    get acceptedCSVFormats() {
        return ['.csv'];
    }

    librariesLoaded = false;
    renderedCallback() {
        if (this.librariesLoaded) return;
        this.librariesLoaded = true;
        Promise.all([loadScript(this, workbook + "/sheetjs/xlsx.full.min.js")])
        .then(() => {
            //console.log("success");
        })
        .catch(error => {
            console.log("failure loading static resource sheetJsPro");
        });
    }

    uploadFileHandler(event) {
        // Get the list of records from the uploaded files
        const uploadedFiles = event.detail.files;
        this.error = undefined;
        this.showMessage = false;
        this.isLoading = true;
        this.fileTitleUpdate(uploadedFiles); //update the file name so we can clean them up
        this.readCsvFile(uploadedFiles); 
        this.fileCleanup();    
    } 

    fileTitleUpdate(uploadedFiles) {
        //console.log(uploadedFiles[0].documentId);
        updateFileTitle({documentId : uploadedFiles[0].documentId})
        .then(() => {
            //console.log('infile update');
        })
        .catch(error => {
            this.isLoading = false;
            // handle error
            if (Array.isArray(error.body)) {
                this.error = error.body.map(e => e.message).join(',');
            } else if(typeof error.body.message === 'string') {
                this.error = error.body.message;
            }
            // this.error = JSON.stringify(error);
            this.dispatchEvent(
                new ShowToastEvent({
                    title: 'Error',
                    message: error.body.message,
                    variant: 'error',
                }),
            );     
        });
    }

    readCsvFile(uploadedFiles) {

        csvFileRead({contentDocumentId : uploadedFiles[0].documentId})
        .then(result => {
            //console.log('result ===> ',result);

            this.data = result.failedRecords;

            if (!result.accounts || this.numRecsToUpdate.length === 0 ) {
                this.recsToUpdate = false;
                this.numRecsToUpdate = 0;
            } else {
                this.recsToUpdate = true;
                this.numRecsToUpdate = result.accounts.length;
            }

            if (!this.data || this.data.length === 0) {
                this.numFailedRecs = 0;                
            } else {
                this.numFailedRecs = this.data.length;
            }
            this.showMessage = true;
            this.isLoading = false;

            /*  Keep this here for Chunk Processing reference 
            let accounts = JSON.parse(JSON.stringify(result.accounts));
            let recordsChunks= this.splitArrayIntoChunksOfLen(accounts,100); //split into chunks to process so it helps with cpu limits
            console.log(recordsChunks);
            this.uploadChunks(recordsChunks,0);

            this.isLoading = false;
            this.dispatchEvent(
                new ShowToastEvent({
                    title: 'Accounts processed',
                    message: 'Any failed records will show on this page.',
                    variant: 'Info',
                }),
            );  */
        })
        .catch(error => {
            this.isLoading = false;
            // handle error
            if (Array.isArray(error.body)) {
                this.error = error.body.map(e => e.message).join(',');
            } else if(typeof error.body.message === 'string') {
                this.error = error.body.message;
            }
            // this.error = JSON.stringify(error);
            this.dispatchEvent(
                new ShowToastEvent({
                    title: 'Error',
                    message: error.body.message,
                    variant: 'error',
                    mode: 'sticky'
                }),
            );     
        })
    }

    fileCleanup() {
        // cleanup any files that are older than the value in the Number_Of_Files_To_Keep
        cleanupFiles()
        .then(() => {
            //console.log('infile update');
        })
        .catch(error => {
            this.isLoading = false;
            // handle error
            if (Array.isArray(error.body)) {
                this.error = error.body.map(e => e.message).join(',');
            } else if(typeof error.body.message === 'string') {
                this.error = error.body.message;
            }
            // this.error = JSON.stringify(error);
            this.dispatchEvent(
                new ShowToastEvent({
                    title: 'Error in file cleanup',
                    message: error.body.message,
                    variant: 'error',
                }),
            );     
        });
    }

    /* uploadChunks(chunks,index) {
        if(chunks.length > index) {
            console.log('Processing #chunk '+index+'of size '+chunks[index].length);
            this.processingRec = index * 100;
            updateAccounts({alist : chunks[index]})
            .then(result => {
                this.uploadChunks(chunks,(index+1)); 
            })
            .catch(error => {
                this.isLoading = false;
                this.error = JSON.stringify(error);
                this.dispatchEvent(
                    new ShowToastEvent({
                        title: 'Error!!',
                        message: JSON.stringify(error),
                        variant: 'error',
                    }),
                );     
            })
        }  
    }

    splitArrayIntoChunksOfLen(arr, len) {
        var chunks = [], i = 0, n = arr.length;
        while (i < n) {
          chunks.push(arr.slice(i, i += len));
        }
        return chunks;
    } */

    exportTemplate(event) {
        const XLSX = window.XLSX;
        var wscols = [
            { width: 25, },  // first column
            { width: 25 },
            { width: 25 },
            { width: 80 },
            { width: 80 },
            { width: 80 }
          ];

        var ws = XLSX.utils.aoa_to_sheet([[]]);  //create a blank sheet
        XLSX.utils.sheet_add_aoa(ws, [
            ["Account Id", "Current Assigned Owner Id", "New Assigned Owner Id", "Assignment Reason", "Deal Owner Id", "Assigned To Id"]
        ], {origin: "A1"});   

        ws["!cols"] = wscols;

        var wb = XLSX.utils.book_new();

        /* Write Excel and Download */
        XLSX.utils.book_append_sheet(wb, ws, 'Account Template');
        XLSX.writeFile(wb, 'Update Account Template.csv', {cellStyles: true});

    }

}
SheetJS / sheetjs

PC and Salesforce: Non printable characters populate cells when new headers added to .csv in Lightning Web Component #2512
