Well this is very strange. I called AA again and they called BA who said they were backed up and to be patient!

This is a flight from a summer seasonal destination. When booking using Avios I frequently find that when this is the case and the trip requires an overnight in LHR (less than 24 hours) that the BA website will not display these flights as a through ticket, although a call to the Executive Club gets them ticketed right away. Flights from year round destinations requiring an overnight in LHR never have this issue. Could the issue with AA be that awards from seasonal destinations require manual approval and AA are waiting on that?