You don't have recent betting activity on those platforms. It isn't possible to address the claim of Bitz.io team as unfair for those old bets. I think your account will be blocked or suspended on Rollbit and BCgame if you place bets there in the future.

Unfortunately, I can't see any best place for you where you can raise this complaint. The license authority could have been helpful here, but Curacao license authority won't be helpful here as Bitz.io going to discontinue their journey with Curacao.