Then, at a minimum, I think you should have said "I hope you are serious about that. PLease give it some more thought, and if you're really ready for full transparency, I would really welcome that."
You have to learn to sift the wheat from the chaff. It seems to me she threw a real big morsel o' WHEAT at you there. I could be wrong, of course, and she could have just as easily been offering an insincere PIECE of transparency (think Saddam, letting the UN inspectors inspect just ONE nuclear plant), while she cheerfully carries on her contact thru another channel.
You know your wife best, so I will defer to you. Just wanted to throw it out there for you to consider.