Ran into a dead-end so far, I was trying to get it where I could add a -all flag and have it show the entire map but so far the only one I can toggle the visibility on is the northwesternmost square because it's 0 by 0 and the structures file defaults to that one in the world_data.region_map stuff I think.
Still works for sites that you can't find anyone to point out, which is super handy in things like a nearly dead world as I was playing in earlier (total remaining pop is like 150 or so I think) because nobody has a clue where anything is anymore.
local hid = df.global.world.world_data.sites
for k, v in ipairs(hid) do
hid[k].flags.Undiscovered=false
hid[k].flags[8]=true
end
Weirdly it doesn't unhide the map block where the lair is (so you're still limited to the locally visible stuff from your travels) but it will unhide all the stuff on visible map blocks for you.
Well, not sure if it's revealing the vaults right, might be another flag in there that needs to be flipped, I just copied the settings from some of the lairs I'd found until it worked as I expected.
Probably try to add toggles so you can have it do lairs, camps, vaults, and everything. Still not sure where to toggle map block visibility is though.