The Modern Forgery Hypothesis

[Battler]

Given that you don't accept the text in the Barschius letter to be an adequate description of the Voynich MS, finding one that does fit seems like an impossible task.

Well, there are a few other seemingly encrypted manuscripts that, at the time, were known but not deciphered.  Like the Tables of Soyga. The Rohonc codex even had mysterious illustrations.  

And those are famous because of their material history, not so much because of themselves.  So I bet that there are quite a few more "mysterious undeciphered manuscripts with unidentified plant and astronomical drawings" that have escaped public attention, because thy lack an interesting history, and are just sitting on obscure shelves.  

All the best, --stolfi

To be fair, there could easily be a manuscript that was unintelligible to Baresch, Marci, and possibly even Kircher, but that is intelligble to us now because it's in a language and/or writing system that has since been deciphered, or even in something that we now know is quite mudane, but was completely unknown to them. For example, imagine if they owned a Korean manuscript entirely written in hangul (which certainly existed in the 17th century), it would have been illegible and mysterious to any of them but perfectly legible and mudane to a modern audience. Or, for something geographically closer and more likely to have ended up in Europe - some Persian herbal written in the pahlavi script. In fact, from what we see from their correspondence - even something as mundane as glagolitic would have been bafflingto Baresch and Marci and that was still in active use in what is now Croatia at that time. So what Baresch talked about, could be some manuscript that's completely mundane and nondescript to us but would have been mysterious to them.