Long-time listener, first-time caller...

I booked a flight from Omaha to DFW to LAX, then on to Brisbane, Australia via AA and Qantas leaving tomorrow. The Qantas leg is booked in Premium Economy. The domestic legs are showing as Y fares. I called AA to request complimentary upgrades on the domestic legs (current Gold) and was denied saying I cannot be upgraded on another airlines ticket stock.

1. Is this correct? I'm assuming this means Qantas owns the ticket.
2. Anything I can do to potentially upgrade on the domestic legs?

Thanks in advance!