Unfortunately, according to the conditions of carriage, JAL has the option to choose the rerouting option that they see fit. So they are allowed to refuse rerouting on QF.
(B)Involuntary Rerouting- (1)Unless otherwise provided in sub-paragraph (2) of paragraph (B) of Article 12, in the event that JAL cancels a flight, fails to operate a flight reasonably according to the schedule, fails to stop at a Passenger's Destination or Stopover point, is unable to provide a Passenger with his/her reserved seat or causes a Passenger to miss a connecting flight on which he/she holds a reservation, JAL will, at the Passenger's option, follow either (a) or (b) below:
- (a)JAL will have the option of providing any of the following remedies:
- (i)carry the Passenger on any other flight of JAL on which a seat is available;
- (ii)either Endorse to any other Carrier the unused portion of the Ticket to request such Carrier to carry the Passenger or request other transportation service to carry the Passenger; or
- (iii)effect a Rerouting and carry the Passenger, by any other flight of JAL or any other Carrier or by any other transportation services, to his/her Destination or Stopover point indicated in the Ticket or any applicable portion thereof.
- (b)JAL will provide an involuntary refund in accordance with paragraph (C) of Article 13.
Have you looked into flying via MEL or other US gateways? QF and AA domestic connections may already be allowed by your fare rules.
Also, have you talked to JL directly? Not sure about Amex agents in Australia but the ones in the US are pretty incompetent even with simple flight change. It took 1.5 months and hours on the phone to change my flight a day earlier because I upgraded one of the segments with miles. Agents kept telling me incorrect info and insisted I had to pay a ridiculous fare difference. I ended up paying nothing for the flight change. May worth checking with JL directly what your options are.