1. I honestly don't think Chen should apologize for anything, especially for something that every one does eventually in their life. Those that have been hating on him, "the Antis", were the ones to have betrayed him, they betrayed all of EXO. They pledged that they would stand by EXO no matter what.
2. SM and Chen had already pretty much stated from the beginning he was going no where. But SM, with their new statement, have confirmed what a lot of people already knew, that EXO were aware of this months in advance. It wasn't something that just happened.