Watch: 'Survivor 50: In the Hands of the Fans' Cast RevealedThe tribe producers have spoken. Ahead of Survivor season 50-which features all returning players-host Jeff Probst explained why fan favorites Rob "Boston Rob" Mariano, Parvati Shallow, and more season 40 alums weren't asked back. "We made a decision not to bring any of the winners from Winners at War because we had just seen them and it was a big season," Jeff explained on the Oct. 22 episode of his On Fire podcast, which he cohosts with winner Jeremy Collins.