Alrigh lets say he wasnt happy w the results. He doesnt have a voice in the band to tell Jon that since he's (...was) his writing partner? I dont know man I just dont think any of our theories are enough to answer the question why the hell did he leave the tour like that.
Im sorry but I dont see him upset or unhappy or even bored in the videos of the tour before April.
He's just...there...being himself. Just like last tour?
And the 'Jon told him to' thing...I see no reason to believe that unless it was like 'ask your self if you still want to be here and when you have the answer come back...or not' but since Richie has said he does want to come back I dont see what the problem is right now...shit probably got way more serious than it was at the start.