If you’ve seen real narcissistic abuse, other than the screaming dehumanizing rage filled sessions, (and this makes sense from an evolutionary perspective) the person on a receiving end has a realllllly hard time cogently describing what they suffered without drawing some suspicion to themselves. And when threatened the narcissist will (this is a stupid term but in the literature) have both flying monkeys, and unleash an attack on your character. Recording everything written is probably not sufficient imho.