There's no proof that you have cheated with your referrals and similarly, you can't even proof that you actually haven't cheated with referrals. I don't think its something you can solve if they intentionally don't.
I don't know how much commission you can earn from them but when you want to promote a site seriously, you should only consider the best reputed casinos. Few months back, there was another accusation which ended in no result/step taken from the team.