Wait, there's really no Shadowgate map?
I've had a linked-screenshot diagram, like the Deja Vu one featured in the magazine, sitting around for years. I was using it to outline a Heretic adaptation. I could have sworn I got it from here, but now that I look at the NES index, I don't see it after all.
Anyway, this is it:
(Open in new tab for full-size.)
No credits on it though.
There's also the Spriter's Resource Shadowgate page, which has the individual screens assembled somewhat cohesively across 2 maps, plus additional graphical and animated variations on a 3rd map:
https://www.spriters-resource.com/nes/shadowgate/Those ones are credited to "SmithyGCN."
I'm not sure if any of these are publishable to VGMaps, but if they're just for your personal collection, then there you go.