So? I doubt very much they are in the same plane. There is a whole sheaf of orbits of any particular inclination. They would form a cone whose half angle is 90 minus the inclination. In this case about 33 degrees. Thus the orbits could actually be in different planes as much as 66 degrees apart. The shuttle is lower too.
But in any event, the shuttle is coming down. They've already undocked from the station. The station will remain in orbit, with that same inclination too. The station crew will be fine.
This was my understanding, but perhaps because of where and when they want to launch the missle the shuttle might just have been too close at that particular time. Still it sounds like it would still be incredibly unlikely that the shuttle could have been hit by either the missle or flying debris.
It’s all about the energy imparted to the pieces of the satellite. Invariably some of them will achieve stable orbits. They wouldn’t risk 7 people, even if it’s less than 10% (which I’m not sure it is) not for some stupid international pissing contest. Nobody is that stupid.