This is interesting.I kind of agree, but kind of not at the same time. SAM COULD HAVE SAID SOMETHING if it were true. Just a little, "I thought you were in heaven, Dean" and that would've changed everything. I'm sad Sam didn't ever explain.
I'd never thought of the Voynich manuscript in this way before, but it does make more sense than most of the "mainstream" explanations. It would not be the first time that a group of women created a language for their protection, either.