People are completely missing the point in this thread. This is a civil action where the plaintiff need only prove their case based on the preponderance of the evidence.
The case law is clear and it is linked all up and down these threads so I won't reproduce here. It does not matter if it was a voice actor who sounded just like her, or if it was a trained AI voice that never used a single recording from ScarJo, what matters is if OpenAI intended to gain from reproducing the likeness of Scarjo. Intent is the key, not even how similar the voices are or the source.
Given that the Jury of average joes will be given this instruction directly by the judge, you can almost hear the plaintiff's lawyers case. "OpenAI contacted Scarlett 9 months before release asking to use her voice. She refused. OpenAI contacted her two days before release again asking to use her voice and she refused. Then, just prior to launch the CEO of the company tweets "Her" despite the fact that they could not secure an agreement with my client. The CEO of OpenAI, when engaged in a massive launch and PR campaign, referenced the likeness of my client in a clear attempt to produce economic benefit."
The two contacts before made the case 50/50 from the plaintiff's perspective. sama tweeting "Her" right before the launch is him spiking the football in his own endzone. The defense only has technicalities. At the civil level of burden of proof this is an absolute slam dunk case for the plaintiff. OpenAI will settle for a very large undisclosed amount of money. No way they let this go in front of a civil jury.