Still having this problem myself too. Seeing many flights available on many days on AA.com (AA metal) for WAS-SYD for 90K (not a saver or web special). BA shows no availability on ANY days from Dec 2022 - Feb 2023. Even though they show a few flights in Mar 2023, they still don't include any from AA. On BA, I did try looking for the whole journey WAS-SYD as well as individual legs that were available on AA (DCA-LAX, LAX-SYD) and still no availability.