Wow, I've never seen this question until today. Sorry about that, the site has many new changes and I'm not aware of all of them.
I have no idea why humans can't be frozen for years like frogs. I am of no scientific authority whatsoever, but I have researched all my articles in depth, so it may appear as if I would know this answer. I can't imagine which article would make this question occur to anyone, but thanks for taking the time to ask.