After reviewing your and Overdoz's video, you did withhold information about your involvement with the other cops that were trying to apprehend Ast. According to the rules on cop hunting, if a cop in a group with other cops attacks a criminal, then the whole group of cops can be attacked. Moreover, if you approach criminals as a cop, you must perform your duties especially around other cops that are trying to apprehend criminals.
Therefore, we concluded that the infraction is indeed valid. If you want to appeal this decision, you will need to DM Karbz as they're the only ones that can reverse this decision.