Rip the Gearbox off? Kind of scare mongering aren't you?
The BT doesn't say anything like that at all. It says that there has been ONE bearing seizure on a Koala and that there was no damage to the helicopter or the occupants.
I don't think they are trying to destroy the older fleet, as these parts are still used on brand new helicopters (AW109SP and AW119MKII/AW119Kx).
Check the paperwork that came with the links. Is the Bulletin annotated as having been carried out? It should be, as items in stock were supposed to be checked.
Either way, if the bearings are tighter than the 7.3N, then get them replaced free of charge, as it clearly states in the Bulletin.
Call your local AOG number, let them know what is going on and why you want another replacement shipped Priority AOG. Also ask that they open an internal investigation so that Global stock can be inspected for compliance with the Bulletin. Let your local Tech Rep know so that they can open an Occurrence Report.