Origins of the manuscript in 1420's
OK so i think i've found pretty plausable explanation where / why / when / by who voynich was made. However I dont know latin, greek, or any useful language so decrypting voynich is something im unable to do currently, but the origins can be figured out pretty accurately in my opinion.
Where / when : in 1420-1450 Mantua, Italy. Radiocarbon analysis already proves this. i also saw evidence of the calfskin (parchment) that was traced back to northern italy, so Mantua's close proximity should be obvious. Vittorino da Feltre created his famous school Casa Gioiosa there in 1420's focusing on reneissance humanism, and the manuscript is classical book of just that. House of Gonzaga funded the process, experts say making the manuscript was expensive process at the time but Gonzaga family had the money to do so.
Why: In 1400 Renaissance humanism was very trendy topic, so the manuscript was made to spread information between friendly court teachers. I think it was ciphered because constant wars were commonplace, so it was thought to be valuable information. Other theory is they wanted to gatekeep people from learning this stuff in the manuscript so they could be hired to the court themselves.
Cipher: Mantuan rulers of this 1400's era used different types of ciphers to crazy extent. They coded even letters to their lovers etc. According to https://en.wikipedia.org/wiki/Substitution_cipher Francesco I Gonzaga, Duke of Mantua, used the earliest known example of a homophonic substitution cipher in 1401.
Creator could be Vittorino da Feltre in 1423 with a group of other teachers in his "Casa Gioiosa". https://en.wikipedia.org/wiki/Vittorino_da_Feltre
https://en.wikipedia.org/wiki/Casa_Gioiosa
https://en.wikipedia.org/wiki/Gianfrancesco_I_Gonzaga,_Marquis_of_Mantua