at "https://github.com/xeokit/xeokit-sdk/wiki/Viewing-BIM-Models-Offline"
this line may be wrong
const metaObject = metaModel.metaObjects["3NI6Sp$yf87eKCx0T$FWj3"];
It worked when it is changed to
const metaObject = metaModel.metaScene.metaObjects["3lMSBJ1J9AUQZulZNJl9KP"];
Also the GUIDs numbers in the guide may not be correct.
Also the GUIDs numbers in the guide may not be correct.