The 330 was damaged in LA on the ground.
Even with QF ownership QF wouldn't give them an aeroplane to replace the damaged one, they would need to hire it at exorbitant rates.
The FJ crews may or may not be able to operate the VH tailed aeroplane, depends on the licensing issues as well as what their regulator would require with regards differences GE vs RR etc, don't even know if they could operate it EDTO if it was a dry lease.
If QF crewed it it would be even more expensive and I would venture prohibitively so.
So the long and short of it is that Fiji would be forced to make do with the equipment they have in the short term and if the repair takes longer than expected figure it out from there.
Either way it will be costing someone a bucket load of money and insurance won't cover a fair chunk of it