All the conjecture on liability is missing one big factor: The correspondence between the recruit and the school. If a player commits orally, I believe the school will respond in writing telling the player, thanks for your interest, but we can't make any commitment because the NCAA rules state, etc. Once an LOI is signed, in fact I'll bet the LOI includes wording that tells the recruit exactly what the legal ramifications are when the recruit signs, including what the school can do to get out of the contract.
So, there is no possibility of the player winning a lawsuit because they have already signed away their rights to sue. No school would leave themselves open to legal peril.
1. Schools rarely, if ever, respond in writing and say they can't make any commitment due to NCAA rules etc. That might happen once in ten thousand cases, but that would almost certainly chase the player away from their commitment immediately. If the school responds in writing it might be to simply talk about the NLI process and the contract that both parties will be signing. The great majority of schools will not walk away from a verbal commitment that they have accepted - other than for the type of reasons that are in the NLI (see below).
2. The NLI is a standard form used by all schools. It lists the reasons that the LOI may become null and void. The complete list:
A. Athlete is denied admission. (But the athlete has recourse if he/she clearly meets the school's normal admission standards for athletes but was rejected because it didn't want to honor the NLI.)
B. Athlete doesn't meet NCAA, conference, or school requirements.
C. Athlete does not enroll in any two or four-year school for at least one full academic year.
D. Athlete opts to serve on a church mission or in the U.S. Armed Forces.
E. The school discontinues the sport.
F. A major recruiting violation involving the athlete is discovered.
If a school voided a NLI for some reason other than the six listed above, they definitely could be sued.
