Lauren Sánchez made a splash at her first Met Gala! The former television correspondent, 54, walked the red carpet at the Monday, May 6, event in a custom Oscar de la Renta gown for the kickoff of the Sleeping Beauties: Reawakening Fashion exhibit. However, her fiancé, Jeff Bezos, seemed to be missing in action as she made her way up the stairs. Sánchez stopped to pose for the photographers by herself in the mirrored floral ballgown with a black corset. Luckily, the Amazon founder, 60, was there to greet her as she reached the top of the staircase. Never miss a story — sign up for the OK! news…