Originally Posted by Often1

I do not believe that AA will check bags across tickets, same PNR or not.

Concur can't link anything and even AA's customer service does not "link" in a meaningful way (agent inserts the other e-ticket number in the PNR Notes to make it easier to track you down if need be in IRROPS).

At a minimum, you will need to call Amex or find an more senior (new agents aren't even trained to do this) AA agent to book multiple tix for the same pax into one PNR.