Air France has categorically stated, in the plainest terms possible, that there was absolutely no incident of any sort on the delivery flight.
Perhaps they indeed were telling the truth. My understanding is the incident didn't happen during the delivery flight.
I wonder what Mr Boeing will do when BA asks for 15 777-300ER aircraft (plus options!) but not with that powerplant?
Mr Boeing will tell BA to go ahead and buy the A340-600 that is on a fattening diet and will be some 50 to 60,000lb heavier than the 777-300ER just to match what the -300ER can do.
If you let engine selection to drive your aircraft purchase decision, then that's what you're going to get.