I don't know if you've already thought of this or if anyone has suggested it, but would better results for some of the composites be obtained by using footage from the Empire of Dreams documentary?

They're not the best quality ever, but anamorphic resolution is available for what shots there are. It might improve somewhat over using GOUT-based video. I think the shot of Han with the stormtroopers at the dead end is there, and some of the Battle of Yavin, but it's been a long time since I've looked at that so I don't remember everything it has.

Just something to consider. ;)