If he had respect for women, and not only lust, he would have shouted through the hole to the girls to somehow patch it from the other end. Or he would have kept silent about it right then (and obviously not looked through) and contacted the maintenance later. That way the girls wouldn't have even needed to suspect any violations, knowing nothing about it.

No matter how this case is twisted, it won't turn ok. It's not like a mixed gender sauna at a pool female classmates could knowingly enter.