How should it have been handled? I recall waiting for a flight with Qantas from Tokyo (Narita) in July 2005 (QF22).
The same situation - one crew member short and the CSM (and QF) was looking for 13 passengers to voluntarily remove themselves from the flight.
The carrot? Free accommodation at the Nikko Hotel Narita (Or similar) and a Business Class seat the following night, back to Sydney.
The was literally a riot as the CSM was stampeded by volunteers. From memory it look like about 35/40 people offered to stay-put for the night.
Sometimes Qantas does do the right thing.
BS