Although Frank and Carol pay for their kid's tuition, no college would contact them about a student's grades since college students are over 18. (Like JT) The only exceptions would be if the college student was a minor or if the student has given permission in writing to disclose to the parents.
No college would address a letter by a student's initials. Letters that JT would get from his school would be addressed by his given birth name "John Thomas Lambert."
Frank and Dana accuses J.T. of cheating when he got a B after they found a cheat sheet that Rich had. But if J.T. did use the cheat sheet, he would've got an A+ instead.