But "cleared" means something different than "Ready to play". It just means you are not too hurt to physically walk onto the field. It says nothing about his ability to do his footwork or move in the pocket.
He is cleared, you can tell because he's suited up. But, the coaches don't think he is capable of playing to his ability or playing better than Zander.
There is also the issue of reinjury concerns. You can be cleared to play and still very susceptible to injury.