I was finally able to get down to Rurik today... Consume Corpse still works. I cleared Rurik's whole path, and revealed 3 new spots, plus a stupid spot I missed from the normal path.
I was already at 100% exploration, and my Frost Gate map is clearer than any others I've seen. So, my question to the other cartographers out there is this:
You've got all the I have (I also have 100%) except I don't have the very south east corner, when I went to skirt there when I was explring nothing happened so I left it. Anyway, yeah that looks like a pretty cleaned out map