I think it is less a question of whether the voice sounds like Scarlett Johansson, as that is subjective and arbitrary (e.g. assume you could objectively measure the similarity, what’s the acceptable cut off - 80%? 90%?). The same is true for the uniqueness of her voice.

I think the real question will come down to intention. They clearly wanted her voice. Did they intentionally attempt to replicate it when they couldn’t have the real thing? If so, there is precedent that would suggest they could be in a little trouble here, e.g. https://www.latimes.com/archives/la-xpm-1990-05-09-me-238-story.html