It doesn't seem like he really tried to bail, just, let go and dropped, almost like he passed out (and then snapped back when his back, uh, snapped). The fact that it looks like his ass was on the ground when the barbell hit him probably didn't help either, no wiggle room at that point. I've dropped a loaded bar on myself once or twice (with more weight than he did) but I was always still on my feet, which helped cushion the blow.
In any case, I'm real interested to hear what the man himself has to say as far as what he remembers happening and why he thinks it happened.
Janos Baranyai dislocated his elbow doing a snatch in '08, came back a couple years later competing at euros/worlds a weight class up. Sa Jae-Hyouk dislocated his elbow in London, and Matthias Steiner was the fellow who dropped 196kg on his neck, and yeah he walked it off but he didn't attempt any lifts after that.