They would have copyright for the translation if it weren't itself illegal - §103 of the US Copyright Act. But this may be different in other jurisdictions.
Two wrongs does not make a right. Translations are derivate works which means the new author has copyright, but they cannot be distributed without both the author of the original and the author of the derivate allowing it.
Umm, no. It may be unethical but the "pirates" have no copyright protections for a movie dialogue unless they wrote the movie.