Scott appeared to brush over the idea that you're asking a doctor to violate his oath and kill another human being.

The oath doesn't matter. You can change the oath. If the oath is stupid, I'd go so far as to suggest outright violating it. If there are reasons behind the oath, then you shouldn't violate it willy-nilly, but you also can only argue based on the oath in the near term. On large scale things, you argue based on the reasoning, and if the oath doesn't match up with the right thing to do, you alter the oath.