A Squared, “Never assume the obvious is true.” ― William Safire
The context arises from the suggestion that the crew sensed the aircraft pitch down; however the reported absence of a malfunction suggests that this was not 'airframe' induced. Thus if the pitch change came from thrust reduction, it suggests no or a late correcting control input, which might indicate deliberate intent or poor co-ordination.
The other scenario is that the pitch change was independent of power and thus it was deliberate, but the magnitude was greater than required for a ‘normal’ adjustment of the touch-down aiming point, resulting in a nose wheel first landing.