UPDATE!

Finally was able talked to a SUPER Knowledgeable, SUPER helpful and SUPER friendly AS International Desk Supervisor after the initial International desk agent was totally confused. After a long conference with her supervisor, I was put in direct contact with the supervisor who has been with AS for over 32 years... (so he has seen it all... )

He was able to see the history of the ticketing - He said the Queue Desk has reissued the tickets on Sept 13 at 5:43pm PST.
I quickly realized that was just a "Revalidation" on a System generated Reticketing of the 15 min departure time change on the MEL-LAX flight that had arrived earlier at 3:13pm, but not a "Reticketing" to reflect the flight change on the SYD-MEL flight.

Before I finished my question on that, the supervisor already saw the issue - To paraphrasing his words "I see the Queue Desk validated it BUT WE NEED TO RETICKET IT SO THE PARTNER AIRLINES GET THE NEW TICKETS. Let me re-issue the tickets for you."

After putting me on hold for a while, he told me it was done, and confirmed he has sent a Confirmation to my email address in file. I asked for the new eTicket numbers and that are DIFFERENT from the last set - meaning new set of tickets is indeed issued! The Print Receipt now also shows the new ticket numbers. Yay!

I felt quite lucky that despite today's the initial international desk agent was quite lack of knowledge as evidenced by she insisted QF PNR code was all what I needed, (that told me immediately she needed more training, lol), she was willing to confer with her supervisor after I tried to convince her that wasn't the case because each and every change requires New Tickets on a Partner award. The senior supervisor was willing to talk to me to further clarify things. It only took 2 min before he fully understood where I came from, and proceeded to FIX it.

Whew. I truly feel for the general public who do not know much about the intricacy of the airlines procedures. That should explain why we often see people had to spend long time at the check in counter, due to things needed to sort out at last minute.