I don't see there is any way we will keep Wilson this summer. No doubt he will want to go to a better club (which is just about anywhere) and double/triple his wages. He has had one good season, and if he were to have a less impressive season here his stock would fall. His agent will have convinced him of this, no doubt, and will be trying to place him. Note he has said all the right things about wanting to stay, etc, so that when he goes the fans won't turn on him.
Likewise it is in the club's interest to sell. They can say what they like, but Clarke showed that if someone wants to go, they get their way. There is no point in keeping a want-away player. And, let's face it, why would Wilson want to stay. There is no loyalty in football other than among fans. To players and managers it is just business.