The "Canadian exception" is gone. This is a problem unless you can find a TA in HKG that will issue the ticket for you. Yes, the AA RTW desk can set it up, and yes, you have to tell them to price it for (in this case) HKD payment and that it will be paid with HKD in HKG. Easy if you are passing by HKG and can call into the AA office in HKG city. The AA Airport office won't issue the ticket. And, ensure you don't try to get the ticket on a HK public holiday. The city office will be closed (been there, done that). It took only 15 min face to face last time there (in the AA office) - but that was early in the day.