done to death....
The airliner crossed a road at a very low height, right in front of commuters; there were eye-witnesses.
The parking-lot security footage snapped still photos only; it did not take high-resolution high-speed video. Little can be determined about the initial microseconds of the crash from the "footage".
Jet-fuel residue was found in the area, along with wreckage, such as one of the wheel assemblies that passed very far into the building.
For one scientific study of the evidence, try here. In book form, try here.