I have some sympathy for the casino in so much that it sounds like the s/ware provider has left them in this hole. However, while casinos continue to try and attract punters with “free money”, they have to expect that some players will try to use that for financial gain, and there’s nothing wrong in that if it’s done within the T&C’s.
What the affiliate is doing is clearly unethical, but he’s only passing on information and clearly decided to align himself with the player rather than the casino. Fair enough – you make your own bed in life. What the player is doing may constitute fraud, but if the casino is really struggling, they should stop offering a bonus straight away until it’s sorted – and drop the affiliate like a hot potato. But, IMO, the buck stops with the s/ware provider and the casino should be seeking compensation from the s/ware provider.