That is because exchanges require it as a must, whereas most casinos including duelbits require it when needed, plus exchanges like binance has like a trillion users lol, duelbits doesn't have that many users and don't need that much quick work on it right away. Which means that they could manually check every single case and they can make a decision that way as well.

I feel like there is going to be some sort of situation where it's not even happening at most given times. Like there could be weeks where they do not need to check any KYC at all, why would they want to work with some place or even hire someone specially for this when it's not needed that much.