Originally Posted by saveri

The AA flagship lounge by gate D30 is the only one you should be considering as it is considerably better than anything else you will have access to.
Your check in for Qatar is at concourse E. While not a dedicated one, the security check line has TSA Pre. Once you exit security don't take the escalators but follow the signs to the D gates. Ignore the Turkish lounge which is close to security. Follow the tunnel to the lounge at D30. You will get a card to enter the FL lounge take the elevator one floor up, ignore the Admirals Club to the left and turn right into the flagship lounge. From security to lounge will take you 5-7 minutes. Give yourself 10-15 minutes to get to the gate from the lounge. You will retrace your steps almost to E security, go up the escalator, take the short train ride and you will be at your gate.
Enjoy.