Sherwood wrote: Some of the letters represent Roman numerals; for example, the first word of the second line “FIX” represents the number 49 and “M4VIX” represents 1459.
She doesn't explain why "F" means 4. She says that in the Middle Ages "F" meant 40 (no citation for this and it doesn't align with Greek in which mu is 40, so I don't know where she got F = 40, or why she changed 40 into "4" or "400" depending on how you interpret it).
She seems to be selectively deciding how to value a letter, along with subjectively selecting which characters are Roman numerals and which ones are not.
She also dos not explain how she turned michiton/anchiton into "Vinci reencounter" or how she got from "Vinci reencounter" to "Vinci I reencountered at O Labada".
Da Vinci makes an interesting narrative. But to me, this is not research, it is story-telling.