I do not think Mrs. Clay will wheedle Mr. Elliot into anything—he has already won the war by removing her from Sir Walter’s presence. Mr. Elliot is now only enjoying the spoils. Like Anne, I think over the years he has developed too much appreciation for rank and consequence. He does not wish a second inappropriate marriage where he is unable to love and respect his wife. The only reason I can see which might prompt him to marry Mrs. Clay is if she imprudently provides him with a child—but even that may only secure her a comfortable home in the country and not be enough to make her Lady Elliot. Mr. Elliot seems like the kind of man who would have his cake and eat it too. :)