In emergencies many people experience severe temporal distortion, and I've read about dozens of people who did the exact same thing, pulled the handle, and spent what felt like an eternity for the seat to eject. They often look down at their hands just in time to have their neck snapped forward/down when the seat fires, just .2 to .5 seconds after the handle was pulled. Apparently a lot can go through someone's mind in .2 seconds.
As for the mishap itself, it sounded like there was one big pop and then a series of pops. That sounds to me like a compressor stall (could be caused by anything) followed by multiple additional compressor stalls as the engine attempted to recover. Some aircraft have a feature that automatically inhibits full power on the good engine to help avoid thje kind of assymetric thrust induced departure that we see in the video, but I'm not sure if the hornet has that feature. In any case, the only way to fly out of that sort of thing is to go max power on the good engine and dump the nose down to immediately reduce AOA, and then hope the plane accelerates up to the minimum single engine speed and the sink rate can be arrested before the plane impacts the ground. It's pretty chancy at airshow altitudes and airspeeds, so I figure pulling the handle was probably a better idea than trying to fly the plane out of the departure.
Good thing the hornet has a good seat, too bad the guy got injured hitting/dragging though. It looked like he got at least one good swing in the chute so maybe he whacked the ground hard enough to break his training habit patterns, which sould have had him disconnect from the chute as soon as he hit the ground.