If I understand it correctly, those people died in their own world, then came to a different world where Cecil met them? In that case, those spirits would not be able to show up, as Cecil has never experienced their deaths. This event is really meant to touch upon people whose deaths have shaped characters in some way or form, but it sounds like in Cecil's case, they've shaped him while they were alive (at least, to his perception).

Please correct me though if I've misunderstood something about the situation.