I see what you're trying to say OP, but what it sounds like is something different.
If someone has an opinion or poential insight (from whatever alleged source) about the inner workings and personal relations of the team we should really celebrate the opportunity as a community to move toward a greater understanding.
It seems to me that you are merely questioning the validity or credibility of an individual's alleged source of information, regarding potential rumours or insights as to whether player A does Y or thinks X, or player B enjoys playing poker with Player C.
You're post is more about presuming the capacity to determine the truth of one's statement based upon your supposed individual interpretation of the truth.
It seems more appropriate, given the intent of this board as an avenue for discussion, to instead of discarding outright one's claim to a brother who's girlfreind knows something, to rather ask a question, seeking to clarify the information.
Oh really, you've heard that player X doesn't want to be here? Oh, where did that come from, what makes you think that? The poster or presenter of said information can then reply, and a civil, democratic discussion can then ensue as to the truth validity or credibility of whatever statement or proposal of fact that was made.
You're post seems to reflect more a dictatorial presumption of knowing what is and is not true. This is dangerous, and stiffling to any community seeking to engage in meaningful discussion.
Yes, perhaps some people make stuff up. So be it. Engage, discuss, question, inquire. I understand your frustrations with rumours that might negatively impact this team. Personally I like hearing the stories, both good and bad, and I can make up my own mind or look further into someone's claim if I want. Afterall, opinions are like a**holes, everyone's got one.