From memory in DRW evacuation after Cyclone Tracy, QF threw seat belt rule away and allowed four pax per treble, plus used one belly hold with ladder access to main deck, and that way got to about 660.
Incidentally, Indonesian Hajj flights require international standards compliance and QF have been in that market for years using standard QF procedures (and therefore relatively high charter price ) - not all Hajji flights are clapped out freighters with kero stoves.