First of all, it doesn't help that you have come off being permanently banned, told the unban was accident and then told it was your final chance.
When the incident happened, another user had been using the command and you are correct saying that Jendo said that they will be warned and I said in admin chat that they will be banned. You failed to explain that I joined your TeamSpeak channel straight after putting this and I heard 2 staff members talking about it. Furthermore, 1 of the staff members started to talk to me about the message. Because of this, it is obvious that you knew about the punishment before you even started righting the command.
The final point is that you didn't just /demote 1 person, you did it to 3 different people in 5 different incidences. Them people were Loaf, Zab and Sandy. Loaf was the Event Planner who was hosting the event and you stopped him from doing his EP duty for 2 minutes. Zab was Staff of Duty and you restricted him from doing his staff duty and Sandy who was the leading battalion. Because of your actions, you stalled the event completely for a couple of minutes.
To be honest with you, you are lucky that the ban wasn't longer.