The reports of the time were not wrong. They just do not contain the level of detail regarding the sequence of events after the initial impact with the railroad embankment that you wish to know.
The purpose of any accident investigation is to discover how the accident happened. The investigators established that the ailerons became effectively disconnected and the aircraft entered an uncontrollable bank after takeoff which led to a turn and descent.
The impact sequence was never something that was of primary concern to the original investigation teams as it had no bearing on the cause of the accident.
As far as the investigators were concerned, the cause was known. The next stage was to ensure the same circumstances could never again cause a similar accident.