So frustrating. I get that feeling from one of my families too.

My dub isn't that far along - he will go in his pull-up every time, but if I catch him when he needs to go he'll go - so I'm not pushing it, but if I thought he was making progress I'd hope that the parents would at least try to continue with my work.

I'd keep dropping hints that they may only be having accidents because they know they have back-up, or that they might not fully understand "being dry" until they know what "being wet" is. Also tell them how well they're doing so the parents might get excited. Maybe parents will take the hint and try it out.