I think you might be missing the point of whether it be ethical, or right, or humane to inflict any form of torturous experience on the conscious copy of a person.

Regardless of the hierarchy of the consciousnesses - if they can still feel pain subjectively, where does the line get drawn as to what is right?

If they can independently think/be sentient then they have value to the universe (potentially) and it would be wrong to murder them.