I saw their exchange as well and it seemed wink-wink-ha-ha to me. Even if Rago was being serious, REB mentioned that he won't return to Edmonton until June 2 and I'm guessing Braunschweig's pre-season will start about a month later. I suppose it's not impossible that Braunschwieg would loan him for a few weeks, but I can't see it happening.
What I find perhaps juicier is that if REB plans to be home in Edmonton on June 2, that would rule him out of the CMNT camp and WCQ games in June. I thought he'd have a good chance of being involved this time.