OMG it worked, thank you so much!
You're welcome!
One question, do you know why it exports the model so small, it's almost invisible xD
Like I've said, GR does not decode and export the models, it just extracts vanilla files in whatever format they might be.
The only way to fix it is by removing the rig. If that's the only way to make it look normal, I'm not complaining, I'll do it myself later, just to save myself some time xD
I don't know the actual format used, but all 3D model formats are vector formats, meaning you can surely scale them.
I don't know the software you're using either, but in Blender you can scale the overall world coordinate system, so it doesn't matter what the original model size was.
With other software, for rigs you probably need to scale the armature and not the mesh, that's all (rigged models have meshes with vertices in armature bone relative coordinates).
If the format is GLTF, then you can even simply edit the transformation matrix in its JSON. Or it might have a "scale" key, then just adjust that to bigger numbers. If everything else fails, and there's a "camera" key, delete that JSON block so that your software should use its default camera settings.
Anyway, this is a matter of the 3D model format, and has nothing to do with GR. I would suggest Blender, because it can import all common formats (might need a plugin though), and then you can scale the model to your liking and export in whatever format you want. Removing the rig shouldn't be needed.