The VMS has something to do with the court of Borso d'Este

[MarcoP]

Don't you find it interesting that this is another manuscript (other than the Balneis) that prominently features large amounts of bathing naked nymphs?

Naked persons as souls certainly is an interesting concept. It was discussed a few times in the past, e.g.:
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Apparently, the idea of nymphs as souls dates back to Robert Brumbaugh (1930s)
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The Commedia was very popular in Italy and it doesn't have any specific connection with Ferrara in particular.
The Illuminated Dante Project has a list of ~100 manuscripts:
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Plus the Cadamosto connection must count for something too.

I am not sure about what the Cadamosto connection is. The bathing images at post #1 are not from one of Cadamosto's works, they are from various bathing texts including "Bagni de la Poreta" (modern Porretta) that were copied together with works by Cadamosto only in the single Spencer Collection copy.

You are not allowed to view links. Register or Login to view. wrote an essay about the Porretta baths in 1351, but I don’t know if the two texts are actually related. De utilitatibus aquae balnei de Porrecta aka Recepta aquae balnei de Porrecta

I love Cadamosto’s herbal, but it’s worth remembering that it appears to be about 30 years later than the VMS.

What if someone from Este's court, some amateur with access to his vast library, used it to copy some images and then create the illustrations of the VMS? Can be someone provincial, sure.

I don't believe that this is entirely impossible. But I am not aware of any specific evidence that could support such a specific hypothesis.