Spouse abuse is a crime.
It is the duty of the others in the room to turn him into the police, not accept him as a repentant sinner and let it go at that. The Lord was in the process of delivering these Christians from legalism to His mercy and grace. Such a betrayal of this man's confidence as you suggest would not have occurred to them. The teachers of the law brought in a woman caught in adultery. In those days adultery was a crime.