Hmm...maybe if it was "In Need of Elvish Medicine."
I think the idea is really neat. It is as if the companion is on leave to be healed and then can come back. Of course, you can play new copies from hand or play the copy stacked on the card. With your "make the site a sanctuary" condition, it has some extra play.
Of course, if it gets discarded and you are counting on that to "hold" your companions for you, you may be boned.

and two thumbs up.
-wtk