As a BAEC Gold/ OW emerald on a Fiji ticket SYD to NAN (Nadi) can I use the Qantas First lounge at SYD?
No. The only alliance-wide oneworld connect benefit appears to be priority check-in for status passengers.
The only way to access the QF First lounge on a FJ ticket is if you have Qantas Emerald status and on the Qantas code-share.
Oneworld appears to be nothing more than a marketing stunt.