Appears that high angle-of-attack, low airspeed pass has no room for error / malfunction. There's some thrust-vectoring jets now than can do that maneuver with almost no forward ground speed (and I'm not talking about the Harrier...) F-22: http://www.youtube.com/watch?v=e_Q6Vb9xJM0 Russian Su-37: http://www.youtube.com/watch?v=1GdfnTLKcvM
I thought about an unrecoverable stall as well at first, but the first witness claims to have seen sparks out of one engine. If one engine lost power suddenly, then the yaw force would probably be too much for any recovery at that altitude. No room for error as you mentioned.
