It's very significant that Kimbrel hasn't signed yet. It tells me that the Sox aren't the only team thinking that K's expectations are too high. A good many things influence those expectations; MONEY, length of contract, the city, the other players on the team, a chance at a ring, how management is perceived, they all come into play (but notice that MONEY is capitalized). Sooner or later K's expectations will meet the offer of a GM someplace and he'll sign.
My best guess is that DD has an open line to K's agent and the Sox will get a shot at him yet. The only question is whether they'll get together on a price.