A couple of observations after viewing the various videos.
Just like the Manchester air disaster of the BA 737, in the last few seconds of forward movement the aircraft skewed/turned perpendicular to the wind causing the flames to fan across the rear fuselage. Possibly caused by one engine still running. It probably sealed the fate of some unlucky souls who may have otherwise evacuated.
There were gaps of in the evacuation line coming down the slides, could this be due to PAX retrieving their baggage or just panic and pushing due to the situation.
R.I.P all lost souls.