Yeah, well, I can't think of a good one, unless maybe it's heart attack or stroke while gettin' freaky with Charlize Theron.
In situations like this, the EDC or emergency items carried by the victims would be nearly useless due to their injuries and the positions of their vehicles.
However, I think the gear carried by the folks nearby who were not involved but rushed in selflessly, in some cases putting their own safety at risk, to help - that gear might just come in handy. Knives, punches, prybars, and especially first-aid, supplies, blankets, and water, would be very useful until the pros got to the scene.
I wonder how long it took for fire and rescue to arrive on the scene? It was the middle of the rush hour, and the traffic was practically at a standstill as it was, but the disaster probably caused gridlock for miles in all directions and made it tough for the rescue workers to get there. It's in that gap, the time between the disaster and the arrival of professional rescue help, that our EDC gear can be vital to the survival of the victims.