There are only two reasons with it it's the part of the mistakes of the player because they didn't even read those permission, terms and rules of the platform
What OP pointing out is that, even a player didn't violate any, the site will counter that the player violated one of the terms. I understand OP on that part as that was unprofessional and users don't have any choice to do. It eventually leads to OP that there should be an authority that will handle it.
However, since crypto gambling was mostly preferred by others because of anonymity, it's somehow irrelevant to hope for an authority that will handle the case in a decentralized world.
We are talking about casino here which is regulated by gambling regulatory board thru providing license to operate. Crypto is really anonymous as currency but it was use on a regulated service so it means that you are not anonymous anymore.
For now, there are still lots of regulated crypto gambling site that's not forcing their users to provide KYC. The majority is still anonymous. Even with that setup, there's still a question on how that main authority to be built. Let's say all crypto-gambling sites are now KYC mandated, in the event that users wants to report them for any fraudulent activities, does any government body can pressure those regulated gambling sites?