Longer version: he knows a heck of a lot, is rather chill, has been in Nautilus for a long time... actually knowing who he is plays a rather small part in it, really.
Morty super mad respects V as an elder, both in age as well as being a veteran in Nautilus. It's very apparent that V is experienced in many aspects of life, and Morty respects that. And being such a fellow buff on history is a huge plus too :3c
showsparrow: Morty is such a good egg and pleasant person. though now I kinda wish he'd been in earshot when V was admitting he's no longer sure how old he is