Firstly Marky, and I am not associated with WGT in anyway, the message you are getting is a general message sent to all members in moderation.
It will be a general message advising the posting guidelines.
Quitters is an issue, particularly at lower levels. Typically gamers are more likely just to leave, whereas a golfer will persist, however some will quit as they are trying to protect an "average".
My experience is WGT will investigate players who are abusive, but without evidence (such as screen shots) it is difficult to prove and is one players word against another.
My advice is to friend like minded players and play with them, best of all be in a CC where activity is high and generally people will not quit. If you do find CC members quitting - I would report them to the owner...and if anyone is abusive, ensure you get screen shots.
When I have come across players like that, I ignore the chat and try and play my best - nothing better than a abusive player getting his ass kicked lol....
Also bear in mind, even quitters spend money, so as a business, WGT will not want to punish unless there is a clear breach of the T&C's.
And no company will disclose information of an investigation - they too are a customer with rights to privacy.