Edit: to clarify, since it is not exactly identical voice, or even not that close, they can plausibly deny it, and we never new what their intention was.
But in this case, they have clearly created the voice to represent Scarlett's voice to demonstrate the capabilities of their product in order to get marketing power.
When studios approach an actress A and she refuses, then another actress B takes the role, is that infringing on A's rights? Or should they just scrap the movie?
Maybe if they replicated a scene from the A's movies or there was striking likeness between the voices... but not generally.
The scenario would have been that they approach none.