"But NOT a safety issue."
Of course it's a safety issue. If an engine is not cooling properly it evaporates the oil, dries up the bearing and bingo the engine explodes.
The temperature rise is not linear. This happens exponentially. If any fault is to be assigned here it is firmly at the door of EASA. They were advised of the problem and elected to monitor rather than halt operations.
Thank God the Qantas crew were tip top and thank God the three missiles exiting the engine did no more damage than occured. BARIT you really do need to read up on basic physics, or alternatively, steer clear of energy based concepts.