Well, Dallas won't be a player in the FA market, because they won't have cap space next season...but they still could decline his option, as he has had some issues. My guess is he won't be on Dallas at the end of the year though. I have a feeling he will be traded.
But whoever has him at the end of the year, if they make him a FA, I would go hard after him with the MLE, because he would be a GREAT pickup.