Booking other non-partner airlines via AA

Quick (and maybe crazy question)

According to AA.com it is possible to purchase tickets for any interline partner through them -
https://www.aa.com/i18n/utility/eticketoppmirror.jsp

I want to use AA to purchase a United ticket using a credit from a cancelled reservation.

I have called the airline main reservation number and they don't seem to acknowledge that it is possible to book any ticket on United through them (let alone using my credit).

Has any one ever done this (either with a credit from a cancelled reservation or without)?

If so, any advice on who I should contact or how to make this happen?

 

I haven't, but I know someone who tried to do the reverse and UA told them no. Credit was only good for UA flights. Let us know how you make out.

 

I know it shows up sometimes when you select "all airlines" in booking online, however I would be surprised if you could use that credit to purchase flight on another airline. Good luck.