According to Dave Meltzer in the latest Wrestling Observer Newsletter, only a handful of people knew about Roman Reigns' cancer diagnosis and not even Seth Rollins and Dean Ambrose were in the loop. They were only told that he would be opening the show by vacating the Universal title and the duo was asked by The Big Dog to be ready to meet him once he was done after his promo.
Michael Cole also knew that Reigns would be vacating the title but wasn't sure of why, while Corey Graves and Renee Young were seemingly left completely in the dark as the show went on the air.
It's said that Reigns requested a bus for the show and was in that until showtime. Vince McMahon wasn't at RAW but worked closely with those who were there. However, he knew about the diagnosis last Thursday and made sure he was in constant contact with Triple H and the production team to ensure everything was handled the right way. Dean Ambrose's heel turn was not originally planned.
However, it seems like WWE wanted to cash in on the emotion of Reigns' announcement by having the Lunatic Fringe turn on Seth Rollins to close the show which, to be honest, was a bizarre move.