The only unrealistic thing is that the player hasn't left your team yet. Imagine in real life a coach telling a freshman, "I want to redshirt you". Player says "no, I want to play". So the coach decides to sit him at the end of the bench, not getting a single minute, and after every game call the player in his office and say "now you want to redshirt? how about now? how about now?" over and over x 30. You think at the end of the year the player would say "ok cool, no hard feelings" and take the redshirt without consequence?
In real life your player probably would have left the team 20 games ago, and if not he certainly would transfer after the season.