So let me get this right - the manufacturer already had a modified TR hub which was supplied to the Canadians and the Japanese but they chose not to fit or retro-fit them to the RN or RAF Merlins.
If this is true then they are directly responsible for the Culdrose accident.
Something similar happened following a fatal Lynx crash several years ago, again a TR malfunction (this time the drive shaft). Only after the event did it transpire that a known weakness in the bonding between the aluminium tube and the titanium forging was being gradually eradicated by replacing the TR shafts with modified ones. Unfortunatley for the crew involved, theirs was not due for change and failed catastrophically.
Automotive manufacturers have to recall faulty products (a consequence of Ford trying to ignore splitting fuel tanks and being sued monstrously I believe), should aviation not play by the same rules?