I have made some findings about this before if I remember correctly. There are people that have sued gambling sites before but the result has always been the gambling site winning the lawsuit. So just know that if anyone sue any reputed gambling site, the gambling site may win the case.
This is because these gambling sites have rules and regulations that intending customers sign up for when they are registering on the casino platform so this makes it complicated for any bridge of trust that will be raised by the customer because the casino will be holding on to the point that you signed up on their platform so you have no legal power over them for what ever thing that happens, it's like selling your rights by signing up on most of these casinos but there are also reputable casinos that has good ways of resolving issues that customers raise