Agreed that the student should see a specialist at a concussion clinic. We got very different advice from that person that we got from the ER doctor. In my son’s case, he was seen at the clinic over a period of 6 weeks. To release him, they wanted him to be able to do certain balancing exercises that he probably couldn’t have done even before the concussion. Technically he was never released from their care for that reason, but the advice they gave (such as lowering the brightness of the laptop) was useful.
BTW, the health risks from quitting exercise should also be taken into account when advising students to quit a sport.