Expert Opinions on 'daiin'

[ReneZ]

I question whether rarity is so relevant in this context and in the context of the Voynich text as a whole.

il represents about 0.02 % of all (composite) characters in the MS.

In a cipher letter of 500 characters, a character that has a frequency of 0.02% has a probability of appearing in this letter, at all, of 0.1. It may appear in one of ten such letters.
Clearly, it plays no role at all in the approach to solving the cipher.