I think I may have some good news.
I pulled-out a Superb ( Anastigmat Skopar, s/n 32670xx on the side of the shutter housing) this morning, and looked inside.
The rear element group is set DEEP within a threaded barrel, which moves in & out with the focusing helical.
I see no spanner slots or other means of removing it from the rear.
All that said, it would seem that your example is "complete" as far as the taking lens train goes... 😉
That said, if the focusing scale on the viewing-lens bezel disagrees with the image you're getting at the film-plane, then I would suspect that someone in the past "worked on it", and got the viewing and taking lenses out of focus-register. With the geared focusing connection between the viewing and taking lens-mounts and the MANY helical leads on the lens helical, this would not be difficult to screw-up ( sorry about the pun ! 😛 )
Using the Ground glass, run the taking lens through its focus range: if it will focus to + 100 ft / Infinity, and down to a little less than 3 feet, it would seem that your taking-lens group is intact, and that there is mechanical discord with the viewing system.
I'm still scared to do anything to these beyond loading film and taking pictures. 😀
Good luck !