I don't think I would. A friend of mine died a couple months ago, and during one of her previous episodes (she had lupus), she totally freaked b/c my gf left the doctor's office while she was under anaesthesia, and was alone when she woke up.
She was so freaked because she didn't want to die alone.
So when she died, we were all there by her side. We made sure she didn't go off alone.
So I say let the killer die alone. Why should he have his life validated by people witnessing its end? He should die alone, in darkness, in pain.