I looked at this some time ago and at the time all who were complained about were blacklisted because all the casinos ignored the letter from there.
Maybe it changed.
To have a successful watchdog site you have to have the cooperation of the operators. To get that cooperation you need to meet with them and establish relationships. They are not going to start negotiation with everyone who fancies being a watchdog.
Something like this takes time and patience, and I doubt many operators are even willing to deal with more than one watchdog.
That’s just my take on the situation.
You also have eCOGRA who is watchdog for it’s approved casinos, and you have the IGC who has mediated in a bunch of cases. These two do so quietly and the cases are not publicized. RTG has it’s own complaint department now and that seems to work.