OK, so here?s the deal IMHO.
If Party A does not trust Party B, for whatever reason, then Party A needs to make a considered decision. And I think the choice, albeit very black and white, is stay and get over it or leave.
If there is a complete lack of evidence, I would strongly advise not to go looking for it anyway. You don?t trust them, that?s the point. Looking for it is only going to make you look like a mental health case if there?s none to be found or, if you do find some, it will just prove what you thought anyway so you may as well save yourself the pain. And Party B will not thank you if there is no evidence ? it will royally piss them off and they may well leave you anyway.
Agree? Disagree?