So both aircraft were in an emergency situation, they both busted minima to get in to Mildura. And the 'legal' fuel you talked about here wouldn't have got them to a legal alternate with any fuel reserves intact.
Mind you, I don't criticise either of these crews, quite the reverse actually. Steely-eyed missile man stuff getting both those aircraft on the ground safely. But painting the Qantas flight as 'legal' and the Virgin as not is disingenuous.