@Astolord
I decided to check the model, both PMX and FBX.
The FBX lacked any and all bones as well as weight paints and shape keys.
In other words it was a completely "nude" model. (For me that means it won't function at all as a VRC model and would be purely static. Its just what it is a model.) Rigging it isn't really a problem, its everything else that is.
The shape keys, the weight paints, the visemes. Anything that Zy0n7 would have already had on the model.
Now for the PMX version. It does have its bones considering it has its weight paints. (If it didn't that would be kind of strange...) It however doesn't have any of its shape keys. So its a step up from the FBX that was seen inside of the folder.
This tells me the model was improperly exported causing it to lose all of its shape keys.
I'm not sure where you got this from or who, but clearly something went wrong here.
If you bought it from Zy0n7 then something must've happened on your end.
If you did not and gotten from someone else then I highly suggest you talk to that person or just simply share the blend file instead in the hopes it has all what its meant to have and you weren't either horribly ripped off by someone or Zy0n7 (which I hope isn't the case) and someone who knows what they are doing in Blender when it comes to models can properly export the FBX with all of its needed contents.
