Are you sure it's the hatch itself rattling, and not the trim on the hatch? I had to fix a nasty rattle on my 210 wagon. It turned out to be the carpeted trim panel which covers the hatch. Hatch itself was fine. Frustrating problem, I seriously believe this is why the previous owner traded in the car. Fix is ugly, but very, very effective.

There are two adjustable "legs", for lack of a better term, on each side of the hatch. You can try extending them to give a bit more pressure when the hatch is closed. They are in plain sight with the hatch open. A single 8mm (or maybe 10mm) bolt anchors each.

- JimY