Also this dating only shows when the pages were made
not when the book was written/printed.
Very good neighborhood at the time I assure you.
He had money to burn~
True enough, but having some knowledge of manuscripts of the era, I would caveat that the preparation process for vellum and parchment are fairly rigorous and elaborate, and it was such a hot commodity that it wasn't laid around and kept in storage, but generally used as fast as it was produced. In fact, palimpsest pages are fairly common...
...because of the value and relative rarity of vellum, pages would be scraped and sanded to be re-used, leaving latent images of the previous text and images behind.
With that in mind, the Voynich manuscript is all the more curious as the time and resources that went into it would point to some wealthy patron or benefactor behind it's production.