Miia explained this pretty good. It's KOSable to kill an innocent no matter what to prevent some "errors" in the gamemode. People can ask you for the reason and trust you but sometimes they don't trust you. Though I don't know if Dingo did open a chat and explain to you or not. He should've opened a chat and explained the rules to you so that you understood the situation.
When it comes to you asking if you could kill him or not and he answered yes. He meant that according to the rules you could.
This can be locked as the question is answered (what I see anyway)
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