I remember there are forums to take care of such fraud in forex industry. Here in this forum as well people will try to provide you a resolution if a casino's representative is available here. In my opinion, open discussion based resolution will be appropriate as it will not be misused and there will be no cost to anyone. But, the catch here is, we need to play only on the crypto casinos which are concerning about their reputation on this forum. This is like playing on a licensed casino hence not a hard rule for following.
Simply, choosing a reputed crypto casino that is having their official active topic here will address your concern as if you face any problem then you can open a topic with all details in scam accusation section where this community will investigate based on all the proof you provide to a resolution.
That's severely limited to casinos here though, and most of them are even crypto casinos, online casinos that use fiat aren't included on the list no? Plus it has no legality included. The idea is really nice tbh, but an online court is not something we'd exactly need since it needs a centralized organization around it. It pretty much says that ALL types of casinos should be licensed and registered to that organization so that they can keep track,, and when issues arise, they can then do the court stuff about it. Highly doubt it would be allowed, different countries have different laws about gambling after all.