What would delaying give us, aside from more ammo for naagloshii? It doesn't want to fight us, yes. It wants power over us. It has intellectus in regards to torturing people. Psychological warfare should apply as the sub-topic.
Right now we have some small chance of having an element of surprise. I don't want to give it up.
Notably, no one, not even Michael, is suggesting to talk to it.
Let me try one more time:
This asshole has had his minions running around town for months.
He's been collecting information. He's had setup time. He even has the details of Molly shanking a Walker less than three weeks ago in the White Court.
We dont know what contingencies it has in play.
Like you yourself pointed out, having an auto-trigger death spell on our friends is fairly straightforward, and from where we are we wouldnt know unless we stumbled over it.
We dont know what its motives are;.
We know it wants Dresden, but we dont know if it wants to eat him, or capture him for other reasons, let alone why.
And we killed the only person we had who we could have asked.
We dont know whose behest its acting on.
There surely are a lot more wizards closer to its base in Nevada; its right next to California, yet it came to Illnois, so someone has to have pointed it in this direction. And its a powerful incentive for it to be messing with Molly, in the same city as a Sword.
And we currently have no preparations with regards to the masquerade, to boot.
We are at the wrong end of an information asymmetry.
And our resources are limited; Lydia is out of town right now.
Our best option for mitigating this is talking to him in order to get information from him
Its the same as when Dresden has to talk to Nicodemus. Or the Red Court.
You dont have to like someone to profit from talking to them before taking action
Else we can end up investing effort in one direction and find out too late that we should have been doing something else
Molly wont die.
But there's other lives on the line here, our friends and potentially that of surrounding civies.
Dont commit us to a particular course of action before intelligence gathering by talking to him.
Paranoia is going to make him less likely to kill the hostages not more. They are worse then useless dead.
Their being useless dead doesnt stop him killing them.
He's a naagloshii, a fallen divine messenger/ god of pain and sadism.
He tends to default to torture-murder.