The aircraft still had foward momentum when it hit the ground. The empanage broke of and shattered. This probably sent some debris on an upward trajectory. The fireball probably added some thermal lift. The distance is not that great. That it was burning indicates that it was above ground when the fuel ignited Nothing odd here.
Care to show us siome documentation of the types and size of the human remains found (in your opinion) too far from the site, along with the direction in which they would have travelled, relative to the path of the aircraft? If they were down-range of the crash site, there is nothing odd about small pieces travelling that far. Up-range is different and would be anomolous.