Leadership on D?

Who are the student leaders on D? On the last play, who would have been responsible for reminding the D to NOT go for the INT? Did the D coaching staff not relay that? Youth and inexperience in this case is not an excuse for setting up that fundamental in that situation. They had to set that expectation prior to the snap. Was it and if not, why not? On that play one was poking at the ball the other was full on trying to catch it as if batting it down never entered his mind.