Never heard of one, never seen one.
Are you just arguing to be arguing? I'm telling you point blank, if someone wants to molest you or your child, THEY WILL, and you act like you will prevent it somehow by being vigilant. If these freaks start checking out bathrooms because you can't discriminate, they will loiter there and if cops come by to check them out, all they have to say is "I'm gender confused, leave me alone".
Actually we teachers do monitor the high school bathrooms for many reasons. And yes if a molester chooses to do so unaccompanied females are at danger. Molestation is seldom done in a crowded restroom. As I have said before NO female or child should use a public restroom alone
I will be interested to see who will do the gender checks at the door to enforce the law. You seem confident that someone with no respect for the law will suddenly obey yet another law. I have never seen that to be true.
Personally I think there are less civil but more effective ways to discourage perverts who prey on females. Argue if you wish just not with me.