In the high-tech megacity of Shenzhen in southern China, Prince Andrew looked on as dancers spun and waved streamers to entertain an audience of investors and innovators. It was spring 2019, a gala dinner for the Chinese arm of his start-up competition Pitch@Palace – which turned out to be the last. Within a year, the then-prince would step back from royal life after a disastrous interview about his links with the convicted American sex offender, Jeffrey Epstein. There was a third man in this drama, little known to almost everyone, who was at the event, glimpsed in a brief shot in the official highlights video – David Stern. Warning: this article contains language and details that may offend some readers For nearly a decade, Stern had acted as a key conduit between the two, making connections for them both in the country he knew well, seen as a land of opportunity and potential riches – China.…