If what's in this post is true, this could ne massive! data breach of this magnitude could lead to a significant stock price decline due to reputational damage, financial costs, and investor reactions, my bet being 2-10% drop depending on severity.
Under GDPR, Rolls-Royce could face fines up to €20 million or 4% of its global annual turnover alongside other corrective measures.
My advice? ,To avoid personal liability, cease any unauthorized use, and consider anonymous reporting to Rolls-Royce. Can't go toe to toe legally with RR tbh.
Depends on what you intend to do with the data. I'm a pro bono lawyer in the forum so all I can do is give advice and opinion. Irl you'll have to retain services of an actual attorney