We've been seated in that room many times, and if you have a late ADR then you will definitely be seated here as they clear/clean the main dining room while the last half-dozen tables are seated in the 'patio' room.
The view from here (either this room or the main dining room) is limited at best, even with all of the windows, because folks will line the street outside and stand against the windows waiting for the show. You will also not be able to hear the sound/music inside the restaurant.
Last time we were there during Wishes, we had little ability to see anything but flashes of light when the fireworks exploded, and the backside of countless folks mobbed on the street outside. I do not recommend it as an option if you are really wanting to see the show.