Can you detail what you did to do your "homework"? That would help those of us who have been through it to understand how there could be that big of a disconnect between what you and your son thought and what actually happened. I am presuming your son is a freshman now having regrets from what he thought it would be and what it is, but please advise otherwise.
Did you look online at the roster history over the past 3-5 years? It would be highly unusual for a school or coach to vary much on how many players he keeps each year, and roster churn or "cuts" should be easy to track as well.
Did your son visit the campus during the Fall practice or Spring season to eye his competition at his position and observe team chemistry and the coaching methods? While he would not know of his incoming competition (unless he was able to track PG commitments), just watching the current team speaks volumes if a kid is objective about his prospects to play.
Did you and your son meet with the academic office and possibly attend a class in his planned major to anticipate what his schoolwork would be like and the department's willingness to work with athletes on scheduling conflicts?
When he visited the coach/recruiting coordinator, did he meet the training department and discuss workouts, nutrition and such? Ask what the expectations are for weight lifting and conditioning?
From my 2017's experience, these activities were all essential to him sorting out options, and he was able to identify some coach BS speak before it was too late. It became pretty obvious who was sincere and truthful and who was just trying to pad his roster and the school's enrollment.