for a medical hardship waiver. The rules require no greater than 20% of games (rounded up, so 3 games for football) in the first half of the season. Chuckie qualifies for both of those. The injury has to be incapacitating (which is essentially up to the team doctors to say he could/couldn't play). You also have 5 years to play 4, so if he hasn't previously used his redshirt for non-medical reasons, he should be able to get a hardship waiver.
Of course, with the NCAA it may not be as cut and dried in spite of the rules.