At the opening of the First Food & Bar at The Palazzo on Friday: Kristen Hertzenberg of “Phantom: the Las Vegas Spectacular.” Hertzenberg, who has the role of Christine, and Anthony Crivello, the Phantom, recently signed one-year extensions. Also there: “Jersey Boys” stars Erich Bergen, Travis Cloer and Deven May; Dani Wylie, one of Bette Midler‘s Caesars Salad Chorus Girls, investor Corey Maggette of the Golden State Warriors, actor Mekhi Phifer, former “American Idol” contestant Ryan Starr, U.S. Sen. John Ensign and Dr. Gary Motykie of “Dr. 90210.”