Kane can make the close quarters combat extremely difficult and will very probably kill the Vault Dweller or his followers.
After killing Decker, some (or all) of the remaining guards may surrender. They can be found later in the basement of the Falcon. If engaged in combat again, they will most likely repeat "I surrender!" once again.
If the Vault Dweller talks to Beth after completing this mission and mention that they were the one who killed Decker, she will give them six stimpaks.