Here’s an updated look at the HDTV master vs the Blu-ray:
Blu-ray: https://i.lensdump.com/i/WPdnTP.png
HDTV: https://i.lensdump.com/i/WPdvOm.png
As you can see the blu-ray smudges so much detail, and that once you clean out the compression artifacts from the HDTV master you can see all the missing fine detail.
So hopefully they will either make a brand new 4K DI with re-rendered CGI, and definately not an upscale of the blu-ray master.