I assumed you called the local office? Have you tried visiting them in your locality?
I find sometimes when dealing face to face, empathy will allow some rules to be bend. If you are just words on a screen or a faceless voice over a line, it is easier to just stick to the rules.
Sydney Ticket Office
Address
Sydney International Airport
3rd Floor, International Terminal
Pier C, MASCOT NSW 2000
Australia
Fax
+61 2 9693 5516
Reservations
1326 27
Ticketing
1326 27
Sydney Regional Office (Corporate Communications, Sydney Sales, Corporate Sales, Marketing, Pricing, Administration & Accounts)
Address
Level 7, 16 Spring Street
Sydney NSW 2000
Admin
+61 2 9364 3500
Fax
+61 2 9251 9149