You can just use a name if it wasnt used before, and Ive never seen A "gavril brute'' before so you can just use it.
Yes but it is still a official name in the game in terms of the name "Gavril" being used. They tend not to allow names from official in-game companies because the last thing they want to deal with is the lack of options for names since all the mods took the good ones. On the other hand they are fairly relaxed about it, take the "Ibishu Dove" but you really would need to be 100% clear with them before you just took it
WHAT? There is a ton of mods that use "official" names. By the way, there is far more possible names than all the official cars that will ever be made.