I see that I assumed it was a dorm, but he only referenced "student housing" and "housemates". If guns are not allowed in the dorms as you say, what makes you think they are allowed in student housing? The answer may depend on the exact wording of campus policy and whether housing is on campus or merely owned or operated by the institution.
I agree that birdhot is a poor defensive load and given the penetration issue resulting from having housemates #4 buck shot is a pretty good load. I hope the OP will not confuse #4 bird shot with #4 buck shot.