Many journalists and connected individuals know who parties, who's angry with who and the like but wisely choose to not report on such trivialities. There are many reasons for this, most importantly that they are into sports journalism and not insider gossips nor investigative reporting, which requires effort and legal backing from the journalist's employer.
Did sports analysts and journalists know Galchenyuk, Smith-Pelly and Beaulieu were notable partiers? Of course, almost everybody who is moderately connected does. Are they paid to report on that? No. When some of these players got caught with skanks, booze and the police had to break a fight between Galchenyuk and his girlfriend, did sports reporters report it? Not a lot. They let journalists who are used to cover these type of incidents do the work, as they should.
As 417 said, the substance abuse program is anonymous. Again, some players, journalists and "connected" individuals usually know about that stuff. But you don't causally throw around that a player has entered the program. This was Mario Tremblay doing the wrong move.
Besides, it's unclear if it is in "the fans interest" and even if it was, I'm not sure people would believe it. Even when it is glaringly obvious the events reported are true, you'll find people (especially on HF) who will be in complete denial about it and scream about conspiracies and talk about "the French media" like a crazy person shouting at sidewalks.