This sounds like "an offer you can't refuse." Someone gave him an easy path out which didn't destroy his reputation, didn't create unnecessary drama, but still forced him out because he was not loyal, so he could be replaced. It's a diplomatic way to deal with it, if the only real issue was just a personality clash that couldn't be overcome. We'll never know the full truth, but on the face of it, it looks like he was diplomatically voluntold to leave.