I was the staff member that approved your PK,
You had been placed under FearRP by the recording party and given ample commands and time for you to comply, which at first you did. Until he gave you the ultimatum to drop your firearm. You understood this was your last chance to fight back and you made the risk to pull out your weapon and break FearRP.
I saw this as clear cut and fit the guideline guide for breaking FearRP as explained in depth by @Vixx.