I don't know if there are statistics or not, but it seems to me that the Achilles injury is one of the most insidious in NBA history because it has ruined so many careers of promising players.
As for Hali, I doubt that he will be able to fully recover and perform better than before the injury, even if he has 15 months to recover.
There’s a lot of Star Players that suffer achilles injury that becomes the turning point of their career. Klay Thompson is the most noticeable and recent best example for this.
He never play like before after suffering this injury. Kobe Bryant, DeMarcus Cousins and many become less effective when they suffer this injury.
It’s high chance that player can’t play fully potential already after suffering this injury. This is one of the worst for NBA player that keeps running and jumping.