I'm going to move this to the AA board as it's specific to AA-issued tickets, and the uses of AA credits.
I think you're going to find that AA codeshares will only apply to flights that originate or terminate in the US, or connect to/from AA metal. Your question has more to do with what partner flights can be used with AA credits. Presumably somebody on the AA board will have guidance for you.
Gardyloo
Oneworld moderator