The difference is it wasn't just one bad affiliate. All their referral income was generated by a bot I have seen many times before. It looks like they might be telling the truth about having advertised their link as well as there are a number of random hits on the link that didn't sign up accounts. The active ones all do a free roll one a few seconds after the other in the same order they signed up in and then play multiply BTC with the free winnings, not to win but to turnover as much referral income as they can.

If one of your affiliates turns into an abuser they would signup those accounts under their referral link, not yours. There is no reason they would abuse just to generate referral income for someone else.