All one needs is the last part of the flightpath, the exact location of the crash, the low level winds in the area and the vertical stability of the atmosphere in the area. All this information can be relatively easily sourced.
Could one provide the source from which one would obtain reliable low wind data for the area and reliable vertical stability of the atmosphere data for the area? One seems remarkably confident of the availability of data reliable enough to make some profoundly important judgments.