To use on Omniverse Audio2face, you must export as USDa and make a change at the begginig of the file exported.
metersPerUnit should be equal to 0.01
metersPerUnit = 0.01
reference with the explanation of the fix
Tutorial from Nvidia showing how to do the process inside Audio2face
You can follow the instructions until 11h20, where he exports the mc and xml file.
after that you can follow this video to import the face animation to blender.
Here is all the files that I've tested. The original blend file with the code to create the conversion, the wav with the audio, the audio2fece export files and the conversion to pc2
You can use it as reference to create your own face animations.