A3 has a few limitations on redemptions.
1. There has to be I inventory.
2. The routing has to be non-stop or 1 stop. There can be an extra stop only if it is seen as a fuel stop example being EVA routing AMS-BKK-TPE. The flight number don't change in BKK so it is allowed.
The agents can be fine but they will refer back to the Online availability. You can't book anything funkier than what shown on the website most of the time. Which has it benefits as the website gives weird results when it runs out of 1 stop options.
You can find the availability by slowly going through with A3 search engine but is will be very slow. Easier option is using United.com or Air Canada Aeroplan website. Here you want to look for saver inventory for business it is I. I did a search on united and LAX-HKG partner I inventory prices out at 99k. From you starting points it might be different.
With A3 you redemptions will be limited to main exit points from the west coast (SFO,LAX,SEA,YVR) as if you need the one stop within the US your only way to HKG will be with UA.
The tickets are easily cancellable with a small fee. (€20)
Your status does not impact anything in this process.