When I export my CC3 characters to Unity 2019.3 or 2019.4.  The bones get messed up - they become stretchy, tall and slim.  I attached a screen shot.  If I re-import, it is fine but if I disable the "Auto-Processing" when I'm deleting the jaw bone (to fix the open mouth issue), it does this to the rig.  Any help would be appreciated. I attached a photo to show how it is making my model look like Slender Man.76% of original size (was 664x19) - Click to enlarge

Good morning,
I've never seen anything like it. First try exporting the vase model from CC3 manually to the program and check if the same fault occurs.
You can also send a photo of the original model showing the bones.
Good luck