GLB Animation Data Getting Lost in Reality Converter

Hello :),

My name is Alec and I'm experimenting with the USD file format. Here's what I've done:

1. I used my iPad to take a point scan of my own head (funny I know). I brought the PLY cloud into Blender where I used GeoNodes to instance objects on those points. I also loaded audio into my Blend file because I wanted my head to react to audio
2. I exported my model into Alembic format (.abc) and exported the animation data as well (.mdd). I followed this video to do it https://www.youtube.com/shorts/awArQyvncmU
3. I brought the .mdd & .abc back into files back into Blender and rexported as a GLB. AT THIS POINT I KNOW I HAVE A WORKING GLB MODEL AND ANIMATION (see a link to file here. Warning, its 500MB: https://drive.google.com/file/d/15nQ2eIqhFQtHce5EbwH4_pXq-maR3rKo/view?usp=sharing )
4. I brought the glb file into Reality Converter hoping there would be a seamless conversion to USDZ. For some reason, my animation data is getting lost :(

I don't know what to do. Does anyone know what I might be doing wrong?

Bonus Question: Is it even possible to put audio in a USDZ file in Reality Composer?

Many thanks to everyone out there willing to help!

All the best, Alec