1) Reverse Engineering is often against EULA or Copyright stuff
2) The new studio can't re release it as they lack
a) Rights to the cars/tracks
b) rights to the game engine
3) They'd not be able to resell it either, as they lack rights to all that stuff, and they are effectively selling someone else's project without the rights to it, which becomes piracy (the bad kind, not the part where people DLing 1 TV show are getting killed, the part where they sell stuff they obtained illegally is the bad kind of piracy.)