If it's a concussion it's very unlikely he'd be cleared in time for Notre Dame.
Check out the concussion protocol:
Particularly:
Each NCAA student-athlete with concussion must undergo a supervised stepwise
progression* management plan by a health care provider with expertise in concussion
that specifies:
Step 1: Symptom-limited activities of daily living.
Step 2: Aerobic exercise with light resistance training as tolerated (no more than
mild+ or brief++ exacerbation of symptoms).
2a: Light (up to approximately 55% maximum heart rate); then
2b: Moderate (up to approximately 70% maximum heart rate).
Step 3: Individual sport-specific exercise and activity without any risk of
inadvertent head-impact exposure.
Proceed to Step 4 only after resolution of signs and symptoms related to the current
concussion, including with and after physical exertion.
Step 4: Non-contact practice with progressive resistance training.
Step 5: Unrestricted practice or training.
Step 6: Unrestricted return-to-sport. **
*It is typical for each step to be ≥
24 hours.
**Unrestricted return-to-sport should not occur prior to unrestricted return-to-learn for
injuries occurring while the athlete is enrolled in classes