I don't think we should be so hard on Jason. He's lived his life, actually being careful not to lead anyone on after what happened with Pierre. Nothing wrong with that. Of course he has grown, since he was changing and wanted to have a serious relationship. Unfortunately, he and Luc weren't on the same page.
To me, his apology was not about thinking Pierre was pining for him or only brought on by his own recent hurt. He knew he would meet them and must have thought about it for some time, preparing what to say. To not acknowledge what has happened would have been strange.
For his own sake, I feel Corey needs to think about his reaction to all this. To be so angry after all those years, when Pierre has so obviously moved on a long time ago... That is something he should deal with.