Did our universe exist in "Supernatural", before the Winchesters arrived?

In "The French Mistake", season 6, episode 15 of Supernatural, Sam and Dean are sent to an alternate reality where they are nothing more than actors; no magic, no angels, no hunting. Sound familiar? It's supposed to be our universe, I think.

The question is, does Balthazar create the universe, implying perhaps it's no different to the realities Gabriel created (which didn't exist before it was created) or did it exist before, implying there are extant multiple realities?

Answer

Gabriel is a powerful archangel capable of creating what are more than illusions... his constructs are solid and can affect the real world in a lasting way. When he kills someone looking like the Ferigno Hulk or probes a frat boy, the person stays dead and the frat boy's butt really is sore. And, in the reality he creates for the Winchesters, it's completely real to them, though to those outside of it it may have only lasted a split second. When Dean dies, he really is dying and being resurrected once more (probably quickly enough that Dean doesn't end up in Heaven). But I do not think you'd call this construct a proper universe. The Bobby in that construct wasn't really Bobby, and all the other people present in it were most likely akin to props.

I come to that conclusion because no matter how powerful Gabriel is, Michael and the others would not sit around while he rewinds the clock every morning. Nor would they allow all the thousands of people who die during that Tuesday to be resurrected over and over. So there must have been limits, even if only imposed by his desire to keep a low profile.

However, it's less clear whether non-archangels have any power to create such constructs. Castiel has failed on several occasions to create such things though they could have been helpful to both himself and the Winchesters... and this is post-season-5 when he's at the peak of his power (well, at that point, anyway).

It seems really doubtful that Balthazar could create that universe, under any circumstances.

Personally, I don't consider that one canon considering how they broke the fourth wall for comedic purposes. But if you do consider it such, the power to create such parallel universes must rest only with the most powerful beings in Supernatural (God, Death, and perhaps God-Castiel).

Finally, I should add that the universe in question was not without magic entirely. It was just a very magic-poor universe. The angel (forget his name) was able to contact Raphael... a bum heard a voice coming from nowhere. According to standard physics, that's impossible. Implying that some limited (expensive?) magic was possible.