Well, my son is a freshman, and this was the first game I've been to, so I could not say for sure whether this is a congregation spot at halftime, but from what I could see, even in normal circumstances, it would be kind of a pain to leave the game during halftime and return for the second half; and if you did, I am not sure why you would go to this courtyard, rather than one of the many beer tents and restaurants nearby.
If I were planning to blow up a crowd at haltime, I would go near a gate and toss the backpack through the fence, not plant it in a random spot on campus and hope crowds would show up. Especially with a timer, sonce no football games run on a schedule.
So I'll vote against the theory. From what I saw on the ground, it doesn't make sense.
I think recent evidence blows my theory to pieces. For now I'm just content to have a strong distrust for anything the university pres has to say. I don't by the "lone suicide" theory, and I don't think the kid had emotional problems like the pres was saying. I'm leaning toward Joel either being directly connected to Islam, or a dupe of Islam.