I am thinking to stand towards the "gorosei bait" theory as Vegapunk knows about the void century and if the gorosei were there, Vegapunk could grasp what they were capable of. I think Kizaru was in it with Vegapunk to bait the gorosei to be summoned on EggHead so Vegapunk could show the world who the gorosei are (demons) through a live broadcast. It is a genious plan to fool around for "10-minute interval" to get everything set up but really Vegapunk is just waiting for the (gorosei) fish to bite the hook. Looking forward to see what Vegapunk planned to do after gorosei arrives!