I agree that you'd be far better off viewing Wishes right on Main Street, then turning around, heading out the exit, and take the walkway (to the immediately left as you exit, following the monorail beam) to the Contemporary. It's a 5 minute walk, and you won't have to wait for a monorail.
When you get there, take the escalator to the second level where the California Grill check in desk is located. You'd have managed a WAY better view of the fireworks and none of the hassle. The restaurant will be much quieter for you because people who stayed for the fireworks will be leaving.