Bottom line, the admin used his admin powers to kill those guys and take their stuff. I consider that abuse. If they were messing with someone in the game, your more than welcome to stop them, fairly. Rally up some men, craft some weapons and put a hurting on them. Going invisible and using uber hatchets (which no one but that admin can have/use for the guy asking; if you spawn one, they are destroyed if you try and drop it) is not the way to go about it.
I think its good for OP to tell us that the admin on that server uses console commands in this way, I will steer clear of this guy because he has an unfair advantage and is willing to use it to win.
Now that being said, I don’t know the whole story (I’m not sure what the admin was talking about when he posted the conversation, when OP said “I know what you did was right”, I thought there was no pvp rules, what was he doing?) and the admin can ofc act in what ever way he wants, its his server and that’s his right.