Morten St George Theory

[Morten St. George]

But even so, if you look at the maps on my blog, you would see that 1) courtly-love versions of Gemini, 2) lizard-style Scorpius, and 3) crossbowman Sagittarius ONLY occurred during a very limited time of history.

Wikipedia cites a prominent archaeologist from Yale University:

"[O]ur knowledge of ancient Maya thought must represent only a tiny fraction of the whole picture, for of the thousands of books in which the full extent of their learning and ritual was recorded, only four have survived to modern times (as though all that posterity knew of ourselves were to be based upon three prayer books and 'Pilgrim's Progress')."

Native American literature was destroyed by the Inquisition, the same Inquisition that, in the 13th century, destroyed virtually all of Cathar literature that was compiled during the preceding hundred years. Today, we have no idea how many books the Cathars wrote (probably a huge number) nor do we know how many of them were written in Voynichese.

The point I am trying to make is that an exhaustive search of extant medieval literature may not find VMS sources because those sources were destroyed and hence not available. We know as fact that Cathar literature was destroyed so, unless you wish to challenge authorship by Cathars, I think you are not justified in concluding that the VMS zodiac has limited sources.