Probably because the Elite is an established brand and All In was such a successful event. Naming it the "Khan Wrestling Federation" does nothing from a marketing standpoint. Cody and the Bucks are the faces of the company and doing most of the promotion,
so using their own brand is more beneficial. It will have a stronger connection with fans and other people in the industry. Maybe if Jarrett had gone with "Double J Wrestling" instead of "Global Force" it would have succeeded