chest not so much. I would think he would focus on that more.
You don't think he's been focusing on chest? Of course he has. Problem is, like I've said many times before, no one changes their proportions as a pro, no one. Exception is belly, it can get more stretched out.
Training for symmetry is a myth.

If someone makes a noticeable change in a muscle group it's oil or implants. Overall size and conditioning, that's what you can play with. Even conditioning is so genetic that it's hard to fix if you've been having problems peaking as an amateur and pro.