I hope that anyone who sided with...*Spoilers*

Sardorim

Kenny and let him commit cold blooded murder against an innocent, Jane, also went over and gave Lily a pat on the back when she murdered Carley/Doug in cold blood and let her back in the group with no strings attached. Same situation really, both acting like crazy people who didn't think things through and made wrong assumptions that got someone, who didn't deserve to be murdered, killed and they ended up being completely out of line.

Jane, Carley, and Doug all tried to get the other to back down without violence. Kenny and Lily refuse. The only difference is this...

You can actually save Carley/Doug(Jane) from the blood thirsty and crazed Lily(Kenny) this time, you can finally stop a crazy person from taking an innocent life and Kenny is glad if you stop him.

If you haven't, replay what Kenny said to Lily during Episode 3 after she committed those murders. Now apply those words to Kenny as he is when he's attempting to kill Jane. It's frightening how Kenny describes himself perfectly on what he's become by Season 2 end, huge foreshadowing there now. At the very least he admits that he was wrong to try and kill Jane and you're right to put him down.

It's clear that Kenny is too far gone, which he agrees with, that he's betrayed his own views when he attempts to kill Jane.

Don't let Kenny become Carver/Lily, only you can save him from such a fate. Save Jane(Carley/Doug) and give Kenny the peace he always wanted, let him return to his family.