This seems like one of those things that was done for flavor--note that
Wizard Staff also plays on a Wizard, and both staves in question were taken by their opponent in the movies (well, in the books, anyway). I'd bet that the developers wanted to introduce some sort of staff-stealing element that just didn't pan out both times, and so we're left with vague wording that doesn't make sense years later.
The only possible trick I can think of is playing
FIS on an exhausted
Radagast or Gandalf, playing something that forces an exertion during the shadow or maneuver phase, then use
Strange-looking Men to transfer the staff and kill the fellowship wizard. The individual steps could be prevented, but the actual death is pretty much uncounterable.
EDIT: or even the text on the staff itself; just keep saruman alive until regroup while the staff is on an exhausted fellowship wizard, and you can discard it that way.