Well John captchalogued Casey, so you can do that when alive

You can captchalogue alive things, yes, but consider Casey is a dumb NPC Salamander- Sorry Casey I love you, but Consorts are notoriously dim-witted and kind of act like what they are meant to be- NPCs. So I still think you wouldn’t be able to captchalogue people, specially people who are relevant, but yes like… Maybe Doomed people?