Crowe wrote:
I'd report it to the park staff.
Why? There's nothing to "report". OP stated she responded and he apparently didn't hear. Sounds like he didn't venture far into the building, either, just enough to help out. It wasn't like he barged in and started looking into stalls or anything.
Maybe your tune would change if a male was present in the woman's facilities at the same time as your wife or daughter. I'm sure their reaction would be the same as the OP's.
The guy doesn't belong in there, and I'd be willing to bet the staff at the park wouldn't think so either.
Kids needing help should be taken into the restroom that is meant for their gender. My wife would take our small child into the women's bathroom if I was not around - no one should have an issue with that. The CG facilities are not for families - if family facilities exist, they are marked as such and have a locked door.
The woman should have finished her shower, then taken care of her female child. In this case, the dad needed to "assist" the children in the men's facilities.