Can you use a mix of AAdvantage/Qantas miles/points to redeem for a RTW flight?

Hi there,
I’m trying to book a 140k point RTW flight for next July for 4 pax. Unfortunately I can’t find any flights home (Sydney). I’ve spent hours trying to be creative but nothing is showing availability on the Qantas booking tool. However I’ve been looking at flight availability on AAdvantage and it’s showing some flights (ie KL to Syd on Malaysian). Qantas are saying they can’t see them!
So my question is - can I use the AAdvantage site to book the flights?
Do I need to convert my Qantas flights over to them prior?
Any help greatly appreciated.

Unfortunately, you can’t convert between different frequent flyer points/miles. Velocity/Krisflyer is a rare exception.