They could put 10 pilots on the MRU flight, and as long as the layover says the same, it still wouldn't be enough.
They've known the MRU flight was a disaster almost from the start, because they thought it would be a quick and easy way to put a tick in the ETOPS box for trainees. However, after just a few weeks, the Training Captains rebelled and told them in no uncertain terms that they could get no training value from the flight, as both the TC and the trainee were cross-eyed with exhaustion on the trip back.