That likely wouldn't be on the table in a settlement offer, and it might be a tough sell for the plaintiff class to get nothing or a protracted legal battle instead of an easy and significant payout. Anything is possible, but I don't think a lawsuit's likely outcome in this situation would be a scorched earth fight.
Has this ever happen in practice for well funded company outside Napster case? I am skeptical that training on publicly accessible data can be ruled illegal. Too many side effects including making Google Search problematic.