I would say stop facing top contenders and elites for now and start working his way up fighting bums of the month just to get his timing and confidence back. The guy needs to make a living but to get back to the top again, he needs to take it easy and just keep fighting lesser opponents to regain the confidence, the boxing smarts and fundamentals and timing.
Yeah, he doesn't have the desire anymore and since he's getting starched by ordinary fighters like adonis stevenson that's proof enough.
His main problem is mental !!! changing trainers and blaming others except for himself and that's why is he in the position that he is in now. The last time I seen fought his ass off is probably against Adamek when he won the belt but after that it seems like he's not motiviate anymore and lost the hunger. I think he can bounce back thought but If I was in I would take a long vacation and then take it from there.
sort of too young and talented. best to just keep fighting. he was a world champion not long ago. i think he is still got enough in his head. confidence. cloud-dawson mack-dawson campillo-dawson shumanov return bout. all winnable, all restablishing fights.