Here's a thought…..Why not both? The Attackers would have no way of knowing which event would work, so they did both to make sure. BOTH EVENTS suffered an ATTACK.
Yes, it's looking as if it were BOTH events. Been thinking this since yesterday, and said as much.
And another thing, at the debate, those people who got sick were the ones setting it up and not actually present during the debate. This means something was being wiped on or put into whatever equipment was being used, and the ones setting it up didn't even know it. It was an attacker having access to the equipment, including the debate stand POTUS would use, that did it.