How much less could it have reduced it by. It seems that the BNE flight departs about an hour after the Melbourne flight and then I doubt that there is much until the following evening
Looking at the schedules, I woud have thought that they would have been rebooked on the QF611 out of BNE that would have got them in at 10:25 , so 3.5 hours later than QF94
Being a domestic arrival would also give likelihood , if travelling with baggage, to reduce that 3.5 hours given the (ime) fast baggage arrival on a domestic service