In 2004, François-Henry Bennahmias — then managing director of Audemars Piguet North America — sent his Swiss employers some pictures from the New York social scene. Stars of hip-hop and rap were captured rubbing shoulders with the old-world power players (mostly wealthy white men) who had long been the target audience for top-end timepieces. In one, a pin-stripe-suited P. Diddy drank champagne with cosmetics titan William Lauder at the…