C100driver,
Big difference in being authorised to conduct RNP-AR and having crew/aircraft qualified/current to fly them.
Of the 4 airlines you listed:
QANTAS - don't currently fly to Gold Coast in aircraft that are RNP certified
VIRGIN - Not currently RNP certified.
That leaves....
Jetstar - Not currently flying RNP at Gold Coast (not sure why)
AirNZ - Maybe certified but don't have access to the Naverus plates paid for by QANTAS.
So that leaves one airline currently able to perform RNP at Gold Coast (Jetstar). I would think that a broader solution to cater for all of the other users of Gold Coast, and the significant GA fleet operating from there, is an ILS.
...and yes Gladstone is getting one