After the hit men fake their deaths, shouldn't the movie be over?
Mickey's character "Bird" insists that you must "kill anyone who sees your face", because he feels no one knows who he is - Right? OK, so now that the FBI knows who he is and his mobster boss is after him, the jig is up.
Everyone thinks you're dead - just go away. There's no money in killing Carmen/Wayne anyway...
Most hitmen try to say they have some sort of "honor" code, but "Bird" was just a psycho who killed for no good reason other than hate. If they intended him to have a code, it was poorly written.