Very sad incident. I have many fond memories of going to Reno Races. I have a bad feeling looking at the pics that he might have overstressed the airplane after turning wide and trying to regain his track. The elevator trim tab is gone, which would have caused an instantaneous unloading of g's - at that speed - it could easily take out the pilot going from +5g to any negative g. There's also no deflection at all of any airfoils in the pics I've seen, again, possible evidence that the pilot was out.
757s are starting to age a little, and in the spectrum of probabilities, this is going to happen. Crews routinely train for recovery in the rare event of loss of cabin pressure, which they successfully did in this instance. Congrats to the Captain and FO.