What a sorry tale.
Recognizing several names on this thread, and fully acknowledging the VAST amount of experience behind them (some inherited in the genes?), I feel most strongly that whilst the stall spin was the event that directly caused the crash, the position he was put in by those awful go around instructions where the key. They where the ones that overloaded him.
For those of us with experience it would have been a simple matter. For someone at that level it was obviously totally beyond his capabilities. A tragic and needless waste.