I'm not sure if how a police can literally help you with this as we have tons of cases similar to you from the beginning that none of those case ended up to be police interfered and there are casino owners that be put on jail.
though maybe i missed something but that is what I know happened here, the only thing you can do is to warn people to stop playing in this casino?  and push the forum to have accusations moving so there will be a constant bump against this team so people will not fall into same situation.