QF Never 'dumped' any capacity into GLT when Jetgo started. They canned the 8 SYD-GLT flights a week and added a few BNE-GLT flights (most were previous flights reinstated.)
The overall market in/out of GLT has been slowly weakening for some time (As has just about every other FIFO port in QLD)
Most FIFO types are very attached to their Status/FF points and lounges and want the convenience of being able to travel GLT-BNE-??? at several times during the day, not just once in the AM/PM.
Good on them for having a go but like has been said, they came into the market at the weakest time of the year. If they had the cash to run another 6-12 months, they may have been able to make a go of it.
So what have they got starting from Feb 9 if they are going to redeploy the aircraft?