This is inspired by Red Panda's thread on what to do with Lilly if she shot Ben instead.
My question, instead, is what would you want to do to Ben if he admitted his guilt before Lilly snapped and shot Carley or Doug?
I think this would've created some interesting and intense group interaction while affecting your group's disposition towards you. Kenny would most likely want Ben gone because of Duck. This could be great opportunity to further cement/repair or totally break your relationship with Kenny. Katjaa would be interesting, since she seems like such a kind person who won't act out of vengeance. Lilly would also want Ben gone too, and might even shoot Ben outright. Carley would probably allow Ben back on the RV. I am not sure about Doug since I don't his character well. Meanwhile Clem is watching...
While my heart tells me to give the kid another chance, I think for the sake of the group Ben would be left behind. We have at least two people that would strongly oppose keeping Ben, one is angry Lilly with a gun and the other is Kenny who has the RV. Keeping Ben would inevitably caused further group problems if not bloodshed. By abandoning him, I think it's a middleground on the need to punish him for endangering the group and keeping some humanity by giving him a fighting chance (but knowing Ben, we know it would be a slim one!). If the game went in this direction, hopefully it'll give you a chance to explain yourself to characters opposed to abandoning Ben.