Knowing that there is some capacity within the tui group why would they go to an outside vip charter company?
Only one of Cello's fleet is in executive config ( let's not call the occupants VIPs! ). Their bread and butter work is short-notice subs for the like of FlyBE and CityJet.
G-RAJG's default config is high-density and gives them more potential for near-Europe subs. They've also been covering for Monarch recently.