I also doubt Rollbit or any successful casino will ruin their reputation for just like that since they could earn more revenue for providing good service rather than doing some shitty things out here. Many people still believe that this casino is still a one of the best casino exist so unless people think this way then they are still fine.
They will not ruin their reputation, their business after spending years to build it successfully. Pay the users and attract more new users in future is better. It is a strategy of a trusted and successful casino but they will only pay for valid users and valid bets.
If a users is an abusers and bets are cheating their systems, they will not make payments for abusive cases. A big casino is able to pay big amount for big valid win so it's not logic to say they scam some small gamblers with small wins. And if proofs from gamblers are not enough, I have less reasons to think their accusations are actually valid.
Another great deal is not just the work they put in, but the value they created. If they worked super hard and the casino was not really that good and it didn't worth much then they would just scam and get more, that's understandable, there are so many failing casinos out there even after many years and I do not trust them at all.
But rollbit is not one of them, this casino worths a ton and if the owners ever wanted to sell it, they would make insane profit from it. So, why would they get rid of such chance and value by doing something silly like that? It doesn't make sense to shoot yourself on the foot with doing such action. This is why it is not the effort, but the value they created which makes me think that there would never be anything outside of legit ways.