I believe that on a planet with a population of 8 billion,give or take,you could find at least 30 applicants to star on this show and you'd probably receive so many applications that you'd have to narrow it down to the select 30,cause for the winner the 1.6 million would be just the beginning,they would be famous and there would also be book deals and interviews that they would get always at the sound of a cha ching going off every time the phone rang.
Even with the risk of being raped and murdered people would still line up for it thinking it'd never happen to them,which would make it really interesting once they found themselves surrounded by predators and you the viewer would get to see the oh-shit-its-about-to-happen-to-me look on their face.
And as far as the select 30,the producers would select the most daring,sexiest,most adventurous ones of the group and also the most worst depraved predators they could possibbly find.