QNH1013.2
Unless you were actually there and witnessed the event, it's merely speculation.
You seem to assert as a parallel that if the ATSB or other qualified accident investigator doesn't witness an event then they too are also speculating.
So what about a Coronial, you definition of speculation seems to fit in this area as well !
And again
Stick with the facts as at this point in time there aren't really.
If somewhat brutal and unemotive, the fact is. "The aircraft impacted the ground at a rate in excess of the structural strength of the airframe and the aircraft was destroyed."
If that is not the case, please enlighten us.
Disco Stu