They still may? He only signed for 1/7 last season. Kluber signed 1/8 last season.
The only news I've seen on Wacha was that the Orioles were interested. If not many teams are in on him, it couldn't hurt to reach out even if the Sox only see him as a backend guy. Speculation is that Wacha is waiting on multiple years, while Kluber was willing to sign for one.