Uhmmm. Oni playing both characters is certainly an option, although it would defeat the purpose of the game a bit (it's 2 vs 2, after all).
Looking for a replacement would be fine, although I don't know how many would like to step in a halfway-done battle with a pre-made character. If you know someone, let me know.
I'm still hoping Atriden'll be back. Maybe he's been busy in the last days, after all he's an active player in L4W too (an in the Closed Eye to boot, I wouldn't want to leave that game!)
For now, let's do this way: I'll wait till tomorrow, then I'll send Oni the character sheet if Atriden isn't back. He'll play both characters for this round, and for the next, still hoping that Atriden will be back, we'll look for a sub.
How does it sound?