Yes but in the case of Tuvok's and Neelix's life, there lifes could have been considered lost in a transporter accident. Whilst the procedure to bring them back invovled the murder of another lifeform. There is a difference between a life being lost in an accident and taking a life.
But as you say you basically have two choices, bad allow Tuvix to live and consider Tuvok and Neelix as being killed in a transporter accident and worse murder another being to bring them back.
your premise rests on Tuvok and Neelix being considered dead during that time. If you change their status to "missing," does that change your views?