If you hand in the ring to Carver, he will send his assistant to go handle the problem who is obviously just scared of the Voidwoken threat and wants to try do something. She's not overly rude or aggressive or disturbed, she's just a normal everyday girl trying to do her bit.
If she goes, the cook will murder her there and then.
It's about understanding the lesser of two evils and trying to make decisions that benefit the good people of the world, not the evil ones. Not all of the Magisters are outright terrible and that understanding creates a moral dilemma. Think of all the Magisters you've spoken to in the game who aren't total dicks that just want to try make the world a better place without the extremes.
On the other hand, the cook may be benefiting sorcerers but she's essentially murdering the wrong people and willingly feeding poisoned food to everyone else, she's not just a danger to Magisters but she's a danger to the general society.
And thus, the choice is your moral perspective.
