What regional has the pilots/aircraft to pick up any additional flying right now?

Think about it. By keeping their flying in house AMR can make us (Eagle) do that flying at whatever rate the BK judge agrees to. As opposed to a back and forth negotiation with a subcontractor like Republic or Pinnacle.

Besides, the pilot group at Rebublic is inches away from total implosion. The only real alternative would be Compass, but again they don't have the manpower. Even if they did, Compass couldn't go any cheaper with their rates than they are already at. It would make no economic sense for AMR to outsource.

Lets also not forget that Delta-who Compass currently flies for- would not look to kindly on an agreement with AA. Compass may not want to rock that boat.