I also believe that one of the unsolved questions in this community is how to produce versions of the prequel’s deleted scenes suitable for fan-edits, as having deleted scenes indistinguishable from at least 1080p footage would be a really big help for various fan-edit projects out there.
Your post goes into a similar direction, so may I redirect you to this post of mine:
https://originaltrilogy.com/topic/Best-HD-Versions-of-Prequel-Deleted-Scenes/id/49632/page/2#1345185
I have made some experiments, but my rig here is far too weak unfortunaly. The guy I am quoting in that post employing an Nvidia Titan XP, something my PC can only dream of.
But maybe you can help?