Uh... that's the point of having them OPEN it. You don't get WS Points unless you're the closer. The system is 1 for performing a WS, 2 for closing a level 1, 3 for closing a level 2, and 5 for closing a level 3. So if anyone else closes, you're only getting 1 WS point, at which point them closing a skillchain is kinda a moot point.