If I choose to shoot you with a gun, and have a variety of appropriate guns, it is not the fault of the specific gun chosen that it was used to kill you. I had motive, opportunity, and alternate means available.

If I smashed your head in with a hammer, would people claim the hammer was the cause of your death? Is "hammer caused death" the end of the story, or even particularly important to the related series of causes and effects?

She's arguing that it's not, that Silver's cause and effect analysis is irrelevant because his purported cause is purely incidental. Intentionally inaccurate models were simply an instrument designed to further the self-interest of individuals.

(And further, she doesn't need to provide a "proof" to make this claim. But she does offer a compelling argument.)