That one always just sounded like a PR excuse to me. If there was any significant amount of hydrazine left on the satellite, then it would have been burned to help it maintain orbit longer. After all, that's what it was put up there for.

So the tanks are pretty much empty, but possibly still hazardous if they survive reentry intact. But I wouldn't really expect them to -- big, thin walled thingies.. no way.

Cheers