In Dalton Ross article
http://insidetv.ew.com/2013/08/21/survivor-blood-vs-water-new-cast-and-lots-of-twists-revealed/

He describes the twists like this one:

• First impressions can be key in the game like Survivor, and that will prove true here as just moments after meeting each other, each team will vote one member off their tribe. They will later be informed that these people have not been voted out of the game, but rather will be sent to Redemption Island, which makes its return after having been absent for the past three seasons. There they will battle to stay alive and reenter the game at a later point.

• Confused yet? Well, it gets even more confusing! Jeff Probst will then immediately offer each of the loved ones of the two people voted off the opportunity to trade places with them, meaning that if, say, returning player Tina is voted out of her tribe at the start, her daughter Katie can opt to take her place at Redemption Island instead, and Tina would then join the tribe of newbies.
  

Well in the vidcaps below I see Laura Boneham in her red one piece bathing suit competing in this challenge with the Galang (Returnee) Tribe! Seems that could have only happened if the Newbies on the Tadhana tribe immediately voted out Laura Boneham and Rupert swapped places with her.

So I think the Tadhana (Newbie) tribe voted out Laura Boneham immediately; now to determine who the Galang (Returnee) tribe voted out. I think I've seen every Returnee in challenge VidCaps except Rupert (but we know he swapped places with Laura), Candice, and Laura Morett.