Wirelessly posted (BlackBerry: BlackBerry8530/5.0.0.1030 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)
If you can get to IST for your return trip, I would search united.com for IST-WAS Saver space.
If you want to use your AA/BA miles, I would explore the cost of a cash flight on Germanwings or Pegasys ESB-TXL/DUS, and then redeem either AA miles or BA Avios for DUS/TXL-JFK/ORD/MIA-WAS.