You are not allowed to warn other mods. Staff are never at any point allowed to take action on someone the same rank as them. These are the first guidelines in being a staff member. This situation wouldn't have been there if you had followed this. The rule simply prevents mod vs mod arguments, such as described here. The screenshot did not show the actual abuse, and even if it did: calling you abuser is something you don't get warnings for. Perhaps if he spammed it. But he did it on a local channel in a distant RP area without people around.

Bad report with bad fundamentals.

-support