Custom tags in metadata.js js object?

I have a metadata.js file that exports an object with global metadata. Everything works great except for custom tags.

module.exports = {
        title: 'Website Name,
        desc: '',
    url: 'https://example.com',
    img: 'https://example.com/assets/images/seo.jpg',
    twitter_card_type: 'summary_large_image',
    twitter_handle: 'twitterHandle',
    custom: [
        {tag: 'meta', attrs: {name: 'foobar', content: 'fizz'}},
        {tag: 'link', attrs: {rel: 'stylesheet', href: 'print.css', media: 'print'}},
        {tag: 'link', attrs: {rel: 'preload', href: 'myFont.woff2', as: 'font', type: 'font/woff2', crossorigin: 'anonymous'}}
    ],
    name: 'Company Name',
}

{% metagen
    title=title or metadata.title,
    desc=desc or metadata.desc,
    url=baseUrl + page.url,
    img=img or metadata.img,
    img_alt=img_alt or metadata.img_alt,
    twitter_card_type=type or metadata.twitter_card_type,
    twitter_handle=twitter or metadata.twitter_handle ,
    name=name or metadata.name,
    robots=robots or metadata.robots,
    custom=custom or metadata.custom
%}

With the above, everything outputs correctly except for custom. What would the proper formatting be for this situation, if its possible? I've been running into compiling issues when attempting the above.

Original error stack trace: TypeError: Cannot read property 'toLowerCase' of undefined [11ty] at getTag (/node_modules/get-tag/dist/get-tag.js:17:15)

Any help would be appreciated! My end goal is to add a custom twitter:image vs using the same image for both og:image and twitter:image. I was going to add a custom meta for twitter:image.

tannerdolby / metagen-docs

Custom tags in metadata.js js object? #6