Well, seeing Wilfrid Michael Voynich in E. Millicent Sowerby's book "Rare People & Rare Books" pretty much clinches it for me. She greatly admired and worked for him for a number of years until just prior to the outbreak of WWI which shut down his business in London. What I don't know is whether or not Wilfred Michael was his given first and middle names at birth or if these were new names chosen when he changed his last name. From Emily we also learn that he was a "Christian agnostic" so these names are certainly plausible. In addition, we learn from her book that Voynich and Sergius Stepniak were good friends. I find it interesting that Sergius's middle name was Michaelovitch... In fact Sergius might have been influential in helping Wilfrid escape from Siberia. From E. Millicent Sowerby we also learn that Wilfrid met his future wife, Ethel Boole who was working with Sergius at the time. I wonder what these guys and gals were up to back then?
Sergius Michaelovitch Kravchinski (page down)