I’m inclined to think it’s bogus, but this Dane is keeping the controversy alive.
When it was initially publicly known, it was widely believed to be the real deal. There are however those who refuse to accept things (largely as a matter of personal whim) and will saddle on anything that seems to tear down their bugbears. :’) The RCC in Rome recognized a Bishop of Vinland (as some of the navigationists have pointed out over the decades), so a surviving map shouldn’t be that big a surprise. (’: