Actually Sharon is smart for refusing it, because they DON'T know what Ryan is doing yet (yes Adam & Sharon have been told seperatly but they don't know).
And if Sharon told him 'oh yeah F2', he has that with Sheila to so why would it help her? He has it with both it wouldn't matter, kwim?
And I think Sharon is weary of Adam for the simple fact he promised his vote last week, and voted her out over Natalie.