Wow, I've found the maps too - if you're using Goldmap 1.3 (or higher I guess) the maps are under the 'Other' category as a load of Question Marks.
And I got this from an original Gold ROM - no editing done to it.
So yes, the maps are real. It does seem they were betas just left in. Interesting.
I'm going to have a go at editing warp points to see if I can actually get to the maps.