lol, custom body kits work just like cars, the owner of the copyright has to approve it, meaning the Developers need to pay royalties, before they can simply "add" something.
And, you would have just been better off posting the car types by name, not likely they are going to open each and every image file.
BTW, NFS 2019 is way past development, so if it's not in it yet, you will have to wait until after the game launch. Older games, like Payback, will not be getting anything new, especially anything requiring extensive coding and bug fixes. It's not cost effective for a game that has officially hit the "Bargain Bin".