Well my flight finally ticketed. So count that as two direct US flights booked using Avios. One with Cash+Avios and one strictly Avios.

Both of our ticket numbers changed overnight. Both are still 125, but now my US PNR shows the ticket number and I can select seats, etc.

Who knows what happened, but everything now looks good on the US Airways site and that's all that really matters in my experiences. I've booked quite a lot of US reward tickets from US and UA miles and 1 so far with AA miles.

Good luck to everyone. I did notice I had to search 3-5 times before PHL-MCO would "show up" as I would get a lot of "BA and its partners do not fly this route." I also had to go on the website in a particular order: Executive club->Spending Avios->(Flights) Search and book a reward flight. Under any other way to get there, it would usually fail to show US flights. Ever since I've used Avios to book AA flights, starting in 2010, I've found the search tool to be finicky.