If she has to pick up her bags and recheck in again, as you say 3 hrs is tight. And AA security is more stringent now than before. I doubt that 3 hrs will be enough. I understand why it used to be 4 hrs. My blood pressure would hit danger zones with the "stress." She should check who will be responsible if she misses her connection and whether AA has a second flight if she misses the connection. I say "fire the travel agent!" She needs 4 hrs++++ in my humble opinion.