I agree with you since if people take initiative to file a case and they succeed to penalize those fraudster this gives an idea to other people that they can sue those platforms did something illegal to them.
Since if they just talk and do nothing for sure that they can escape on the charges supposed to be filed to them and people will just slowly forget about those bad actions they have done to their community.
If lots of them got compromised by this casino maybe better if they unite together, so that they can file a strong case against them.
I believe that impunity breeds permissiveness. A punished fraudster will think twice before repeating the fraud. Others, knowing that fraud will be punished, are very likely to abandon their plans for fraudulent schemes, as there is a living example of punishment. In short, I recommend gathering a group of victims and filing mass lawsuits. This will not give a 100% guarantee of a solution, but inaction is guaranteed not to solve the problem.