if he was ejected for wearing clothing that any woman wouldn't have been ejected for wearing, then absolutely fair dues on the discrimination charge, as that's precisely what it is. and good luck to him.
if he was ejected for wearing excessively taboo clothing that anybody would've been ejected for wearing, then he's just taking advantage. on that count, it's nothing to do with discrimination, and is rather a uniform policy and/or public decency issue.