Were these two other unreleased Runaways meant to be two more Superfriends nods, the Wonder Twins? Wendy Marvin?
Maybe set up join the others in a potential later episode?
They certainly weren't Wendy and Marvin since we already know they were at school with Superboy. And the Wonder Twins would lose a lot of what they're about if they're not aliens.
They could've been set up to be villains...not sure who, though.