Valley of the Ancients is the title used for all of the copies of that Map that I have ever seen.
I have never seen a copy of Map 3 that was Labeled "
Glow-Worm Steppes".
Additionally; All of the books (Wilderlands of High Fantasy) that I have (In the Text only) call that area Glow-Worm Steppes, even though the 8-1/2" x 11" overall maps inside the same books name that area Valley of the Ancients.
The Valley of the Ancients is barely mentioned in the actual text of those books.
But, I only have the 2nd and 4th Prints of that book.
Campaign Map 3 is located at the farthest North East corner of the Judges Guild Wilderness Setting.
Barbarian Altanis is on Campaign Map 2, and The Valley of the Ancients is on Campaign Map 3 of the same Double Sided Map.
http://www.acaeum.com/jg/Item0048.html
Barbarian
Altanis is mis-spelled Barbarian
Atlantis on the page linked above.
See the second description paragraph (the link for the maps 2/3).
Valley of the Ancients is on the same side of the map (Campaign Map 3) as the Glow-Worm Steppes with the Valley being directly North of the Steppes.
As for your last statement, I agree with you.
None of the 2/3 Wilderlands Campaign Maps that I have are titled Glow-Worm Steppes.
Of course that does not mean Campaign Maps labeled as Glow-Worm Steppes do not exist.
I only have a few copies of Campaign Maps 2/3 and I am fairly sure that none are First Print Maps.
There must have been thousands of copies of Campaign Map 2/3 distributed by Judges Guild.
I have always thought the label that mentioned Map 3 as the Glow-Worm Steppes on the Sub Web Pages was just a small error.
As an aside, that map could just as easily have been labeled The Plain of Skulls...
(See the northwest quarter of Campaign Map 3).
I do not have any First Print Sets (Books/Maps) of the Wilderlands of High Fantasy.
Perhaps the first prints of those Campaign Maps are labeled "Glow-Worm Steppes"?