I've been wondering this too. The difficulty is how to get the dialogue in without the footage. I think that when they get to full restoration mode on the LD there might be a chance they can fix the footage enough for just a few shots.

Also, if footage is used from the LD, I would hope that a way can be found to include the Luke/Lightsaber footage. I understand the desire for best possible picture quality, but that isn't always possible, and Harmy's Despecialized should be a good indicator that people can still be extremely satisfied, despite the varying quality of source material.