Red:
???
- Did you go to college?
- What specific "they" (designate a job title) do you have in mind?
- Did you not notice that coaches were "in" on the gig? What do you think was going on? The football coach was sneaking in students as members of the crew team and praying the crew coach wouldn't notice, or vice versa?
These were universities, not swanky boarding schools or any other kind of institution that educates minors. (And FWIW, part of what's "prep" about prep school is their willingness to let students flunk out.)
As for whether a student of any prior academic background is struggling or not, nobody is going to notice such a thing because once one's admitted, nobody's who's teaching them is interested enough in their high school performance to bother looking to begin with.
The central administration won't notice anything until their exception processing software programs tell them to send the student notice that they're either suspended or expelled for academic reasons, or that the student's performance is exceptional enough to have earned him/her some sort of plaudit. It's college. The students are adults. Nobody is mollycoddling them. If they perform, they perform; if they don't, they don't. It's all up to the student and the consequences of doing either appear "out of the blue" and without warning. One gets all the warning one is going to get when one matriculates and if one accepts scholarships or other financial aid, when one "signs on the dotted line."