Yet the fact is that a number of passengers were placed at increased risk, due to an un-briefed failure mode, resulting in the aircraft suffering a heavy landing with no-one in control of the thrust levers.
Whether the passengers were exposed to "increased risk" (however we choose to define that) is a moot point and the OP will have observed from subsequent posts that opinion varies widely about that.
But the other two parts of his/her assertion are harder to dispute: yes, it was a heavy landing (per the AAIB) and yes, the potential failure of the prosthetic wasn't briefed (hence the commander's undertaking to do so in future).
Move along, nothing to see here.
Agreed, but before we do so, file under "lessons learned".