I think it's more likely Kristof consulted Judith Miller about the matter. She had been writing about WMD's for a long time and would have had extensive CIA contacts.
Let's suppose, after the breakfast, Kristoff goes to Judith to bounce the story off her. It's possible Judith said something like, "Oh, his wife was there? She's CIA, you know".
That makes sense. The increasiong permutations increases the chances of being right!
I also found this from 2004 which reinforces what you brought to light.
I like the Kristof/Miller connection as well. Kristof's wife, FYI, also works for the Times as a reporter. Oops, maybe I shouldn't have gone there....is she fair game?