Since learning and reading about Crispyfishsticks Locks (that are full of voidy awesomeness shall I say) I always had the feeling that both Lana and Rena would meet/see some of them on their travels through space (well since they are immortal and locks appears to be too, they’re kinda bound to meet at some point ?).
But I think that Rena would have ‘met’ Aryian years before she and Lana started to travel. It’d always be just a glimpse but she’d probably see him once of twice while she was alone.
Since Eadras are the incarnation of black Echo (‘void energy’) they’d probably feel the presence of Locks when they are nearby (or you know, near the Eadras’ planet, floating through space like the space eels they are).