The nozzles may have gone past the normal aft position due to the impact which was severe enough to trash the rest of the jet.
I'm with Mr Farley on this one though. When the jets hovering and the donk quits, it's only going one place and that's straight down - this one didn't. It started to accel forward and to do that the donk must have been producing some thrust. Looking at the video it's noticable that the jet is quite stable with brownish jet eflux - this is normal with the water injection flowing. The smoke stops and the nose comes up before the old girl starts to stagger forward and down. There could be a million causes why either the nozzles ran aft on their own or the engine lost power (water fail/ran out/DECS malfunction/birdstrike etc) but it looks like either a nozzle runaway or a loss of power(not total) which Tony didn't have the heigt to accel away from.
Good to see he got out though - even though he always was a throttle pumping ar$e!