You can try and state things as fact as much as you want to. We now know these men were all ware of a prior investigation and had discussions on what to do. 4 days ago people were still denying Joe was "coach" in the emails. Well he was. He and Curley also had some type of discussion on this case and somehow Tim decided not to make a call.
Some people will have the opinion Joe's conversation may have played a part. Others will deny it completely. Unless Tim decides to clarify it, we may never know. Discounting opinions without proper evidence is fun to do on this site, but it doesn't make things so. Yes he did the right thing in telling Tim, but he should have followed up on the side of caution or stayed the hell out of it. He at least showed remorse immediately and handled the BS way they kicked him out the door with class. Sadly that one decision not to call the DPW by Tim was the wrong one. He didn't do it with malice or deception, but the torches were already burning as soon as this was leaked.