alph2z
PULKOVO 612 Tupolev Tu-154 (85185) seems to have had an AOA indicator and it didn't help them, very unfortunately. Also available, is an official simulator video on Youtube.
That's a different accident. Pulkovo 612 did not have any failed instruments. The official report states that the pilots deliberately tried to climb over a thunderstorm, lost a lot of airspeed in the process, encountered heavy turbulence and hail at FL380 and lost control at FL390. The indicator is there to allow pilots to avoid dangerous AOA well in advance (unlike stall warning/stick shaker). Obviously, it will not help if the pilot insists on flying at a dangerously slow speed, at the aircraft's maximum ceiling, in hail and in turbulence - all at once!!