Former prince. And t's not purposefully vague, the article explicitly says "It comes after Thames Valley Police said they were assessing a complaint over the alleged sharing of confidential material by the former prince with late sex offender Jeffrey Epstein"
If you read through the BBC post, it alludes to passing confidential trade documents to Epstein... but of course that's probably because he was being blackmailed by Epstein for f*cking under age girls.
He's being prosecuted for sharing sensitive information with 3rd parties or something. He was in some cushy foreign envoy type job back then, and it seems he did not really take it very seriously. In the epstein files there is evidence that he regularly shared sensitive information with JE and others.
He's not being prosecuted for raping kids. But maybe new evidence comes to light during this investigation.