Okay, then tell me this: What would you have done instead?
Do you mean, had he been a VOY writer, or do you mean, had he been Voyager
's commanding officer?
Speaking in-universe, were I in Janeway's shoes, I would have held a memorial service for Tuvok and Neelix, filled out their death certificates, and then filed a birth certificate for Tuvix.
And then I would have offered Tuvix the opportunity to serve under a Starfleet field commission if he so chose, or to inherit Neelix's shuttle and go off exploring if he so chose.
In my view, there wasn't anything to be done.