Have you never had an injury recur? Have you never push the envelope coming back from an injury because you have a big meet? If he's gonna be ready to do something, he's got to train and roll the dice that he might aggravate his injury that's not 100% yet. What's his alternative? Not train, so the hammy is 100% but he hasn't done workouts in 2 months?
Sometimes you have to risk it. Seems to me he took a chance and got burned. That's his call, and my guess is anyone who has trained as hard as he has to get to his level would be unwilling to just bag a trip to Worlds without giving it a shot.
I'm not saying he's clean, but I am saying that the scenario that he's dirty is only one possibility.