This kind of superficial category error sets my teeth on edge every time I encounter it: such people seem to think that a "hoax" explanation must somehow also be the most "skeptical". Actually, if they would bother to look at the object (rather than at the EVA transcriptions), they would find that the VMs has 15th century quire numbers, and a complex codicological history. Sixteenth century hoax theories requires that all those many layers of evidence be part of the hoax too: of course this is a "possibility", but multiplying the various unlikelinesses together, you end up with a dwindlingly small final probability.
Instead, a properly skeptical reading would say: "the presence of 15th century hand-writing in the quire numbers is a strong indication that the manuscript was made no later than 1500, while the presence of various art history features in the drawings points to an earliest date of around 1440. Explanations significantly outside this date range would require strong evidence to support them, which has not yet been found or demonstrated. And that's about as far as we can reasonably go at the moment."
What I'm getting at is that the hoax hypothesis displays the wrong kind of incredulity to be genuinely skeptical: it portrays the evidence itself as incredible, rather than "typical" Voynichian hypotheses (Cathar, Alien End-Times, Old Ukrainian, Baconian telescopy and microscopy, Leonardo etc) themselves as incredible. The curious Voynich solution mentioned in one of the comments to the German web-page on Schmeh seems to fall into this general category, sadly.