I think that some people have been a bit harsh and I hope the ACME book of helicopter flying is all I ever need if faced with such a situation, some of us have clearly swallowed it.
Speculation is one thing but none of us where in it with them, over a very congested area with one tail rotor that seems to have caused the problem, I don't think any of us at this moment in time can say what he should have done, I doubt anyone will be able to do that until an accident report appears, and even then perhaps we should limit it, to what he could have done, he may have considered his options to be very limited.
I agree with FH1100 pilot about the smoke that it could have been the pilot turning off the fuel cock/valve whatever its called on an AS350, I have seen several turbine engines shutdown by use of the fuel cock and they all gave a short burst of smoke just like the one seen in the video.
Can I suggest a little more respect for the guy, particularly on the day he died.
May he rest in peace.