Roblox has had also problem with thumbnails for their own accesories (Which some still not fixed.)
Previously UGC wasn’t affected, so now the bug might’ve moved to UGC
There was a bug in thumbnail generation that started last Wednesday through early Thursday that caused camera angles to not be properly reflected in the thumbnails.
This has since been fixed, however any thumbnails that had been generated during that time will need to be recreated/regenerated in order to get the correct camera position.
Please let us know if you run into a similar problem again. Thanks!