Although the high ankle sprain was definitely a wink wink type thing, probably not fair to say he quit. When you're pretty much a unanimous top 11 draft pick the following year you play it safe. Don't fault him at all for that, that game wasn't going to be saved.
I agree. No point to come back in the game at that point. CMC played an injured QB most of the year last year and at that point in the game there was no point as the game was far out of reach.