Hey, if Harmy regraded the Star Wars Original Trilogy, someone can do this.
I think this would be a piece of cake compared to even one Star Wars movie.
Well the issue is that these come from modified CAPS files. If they recolor something digitally you will never get it back. From what I’ve seen of the CAPS films I am pretty certain that in particular scenes they have recolored individual items (characters, objects, backgrounds, etc).
If they didn’t do that then yes you can theoretically regrade the BD, but I am pretty sure there are parts that cannot be regraded. Nevertheless once we have the scan you’ll know exactly how it looks and can do whatever you would like. You can get a copy of the 4K files for the price of a hard drive if you want.