The extra handling of the bike box may cause damage. IME bike boxes are a perfect flat base for all the other bags to be put on top of . Do you really need a bike on LDH? Rental bikes are available and almost obligatory for getting around. Having a "good" bike will invite attention which may lead to its loss (or at least someone "borrowing" it overnight (and usually returning it next morning)) - been there, experienced that (and that's with a rental bike). Nobody locks bikes on LDH.

I'd recommend finding a friendly place (ie bike shop) to leave your bike in SYD, PQQ or BNE when you go over to LDH (given that LDH flights only depart from BNE, PQQ or SYD). Its really too much hassle to cart a bike over there. And, if its offloaded due to weight / space, that'll bring its own dramas.

And, as for an hour on your mobile to QF, try Skype.