Little Witch Academia CoT models?

[Supurreme]

EDIT: here are some sample files

So I know this game runs on unity and i can open and view them in unity asset studio


but whenever i try to export them i keep getting this error on every single model

is it just something wrong with my version of asset studio, or something with the models themselves? ive come across encrypted or compressed unity files before (one piece thousand storm) but not even those did this so idk whats up