FWIW, according to my ticket:
"11. Due to safety considerations, umbrellas are prohibited within the stadium.
12. All bags, backpacks, large cases for binoculars or other items, fanny packs and large purses (larger than 10" by 10") are prohibited. Only such items required for medical or family needs will be permitted. All carried items and entrants are subject to search."
Because of this, my wife did not even bring her purse to the game. I don't recall seeing any backpacks, although I saw purses that appeared to be at 10X10 (which is not all that large, really.) I can't say for sure how strictly these published rules are enforced, but I would honestly be a little surprised if they let in a kid with a full backpack - I suspect they would be searching it for alcohol, not explosives, but I don't think he would have just been waved in.
Do you think he tried?
My OU bag that contained my purse is 12 x 14 and they didn't bother to check it -- just looked in at my purse on top.
Can you say COVER-UP in progress but it is not working? Word is starting to leak out about this not being a lone person who committed suicide.