You've given it more thought than me.
I think that it would be humane to start off with something like the house out of one of the SAW movies. We select a group for testing to see if the process would work and choose people who are definately not wanted in the world. We then put them inside a house with a series of challenges and give them hope that they will get out alive. We then set up cameras and keep an eye on it and publish it on the internet and TV to get money from it.
A bit like a sinister version of BB.
But how would you go about selecting those people that are not wanted in the world.
We could set it in an old prison where they are the only people, no guards. They'll have to learn to support & trust one another in order to make any escape possible. Those that survive the first time get to go back in a second time, maybe a third.
If anyone wants to see what is happenning, forget paying to see it on TV. You get to join them & find out what its like for yourself