From the CV & FDR the experts can recreate the flight using the pilot’s inputs and the aircraft’s controls actual positions.
They should reasonably quickly know if there was a failure of the TRDS, TRGB or TR controls.
If there was a mechanical failure they should be able to check the HUMS data to see if it could have been spotted before it failed. If it could, they can check other AW169 aircraft HUMS data for similar trend(s) (this is much quicker and cheaper than grounding all similar aircraft).
It is vitally important that all parties are open and honest in the interests of Flight Safety. I fear that some may be less inclined to be so. Time will tell.