Theory that the final section is a multilingual glossary

[oshfdk]

Perhaps, but I don't think the two strands play very nicely here. If it is a document for European use, I would expect European glosses as well, not to mention other languages that don't fit the profile of a standard Mainland Southeast Asian language. On the other hand, if those non-MSEA glosses are in Voynichese, that would prove Voynichese is capable of encoding a European language, and undercut the need for the Chinese Theory in the first place.

If I remember correctly, Jorge_Stolfi's answer to this was something like "the original notes of the author could have contained European notes and translations and remarks, but this specific rendering on vellum was specifically designed to only contain the original manuscript in its phonetic form with no extraneous writing". This is not impossible and not even very strange, if one thinks of it as a presentation document accompanied by a separate booklet of notes.

As I said elsewhere, the storyline accompanying the Chinese theory is not totally unbelievable, and I think with some minor tweaks it can be made very plausible. 
For example, if we replace the Reader with the Teacher:
- the Author (European, can speak some Chinese, but cannot read/write Chinese characters well) meets the Teacher in China and the Teacher is enthusiastic about spreading the teachings to Europe, so he agrees to help the Author create an accessible copy of his works
- however, being Chinese, the Teacher insists that the book cannot be translated from laconic Chinese into a European language without losing most of the meaning, or the Teacher simply wants to make sure that the teachings are rendered as closely to the original as possible
- on the other hand, the Teacher understands that it's also impossible to teach the Author how to write the Chinese characters quickly enough
- the Teacher studies Latin writing and decides to adapt some Latin script forms (throwing in gallows as a mix of Chinese forms with Latin letters) to create a phonetic representation of Chinese that the Author could write down quickly enough and also that certainly will make it easy for European scribes to create many copies of this work in Europe
- the Teacher dictates the work and checks that the Author writes it down correctly and precisely without any extra writing, notes or comments in a foreign language, to preserve the purity of the work
- in Europe the Author orders a vellum copy and asks the Scribes to throw in some pictures to make the book appear more valuable

and this is how we got the VMS. I really see no problem with this, especially if the whole work was sponsored by the Teacher (or the Emperor), so the Author was obliged to keep it precisely as it was. However, after making a single copy in Europe the Author wasn't able to find any interest, or maybe died and without his knowledge of spoken Chinese the book became useless.

As a story this works fine for me. However, as far as supporting evidence goes, I think I haven't anything even remotely convincing so far.