No, Disney can have anyone do an online SW game. That's why there's a online clone wars game, and the up coming attack squadron.
they could but I can't see them lisecening out a MMO. I suspect the terms of the agreement where more to allow disney to publish casual facebook and tablet games. which seems to be the direction Disney PERSONALLY perfers to go with video games. Disney's basicly not intreasted in persueing bit AAA video games. thats WHY they handed an exclusivity deal to EA. so EA could persue that "expected" angle of the franchise and leave them more or less out of having to deal with it