Another bit of data: since my wife (who has the new AA#) and I always travel together, the missing reservations and holds are still showing in my account. If I look up those reservations, they are still showing my wife's old AA acct #.
So, it seems like they should be able to transfer over reservations and holds by updating the AA acct #s. I'm puzzled as to why this was not part of the new account creation.