If this is what Redemption Island actually is, then I've seen it in action before. Survivor Philippines had this same twist in its first season. I got used to it pretty quick--the Redemption Island (or in our case, Purgatory Island) resident was a (HOT) post-op male-to-female transsexual who was voted out in the first TC and managed to beat everyone else up until the merge. She managed to make it to the final Tribal Council and ended up in second place.The main difference, of course, is that both Survivor Philippines and Survivor Israel have a substantially longer running time than the US version. The US generally has 40-45 minutes of actual run time. Survivor Israel has 60 minutes, and Survivor Philippines is broadcast as five 30-minute episodes throughout the entire week.
If we do see another challenge in Redemption Island, I'm wondering how they would all fit all this in 40-45 minutes if they need to show three challenges, camp life shots, confessionals, and a tribal council. They don't have enough time as is to fully develop their characters, much less if they add in another challenge per episode. Unless of course, all pre-merge/pre-jury challenges are combined reward/immunity, making each episode only have two.