I doubt it's true but there's a possiblity that....
That the actual cast is being played, not Chase. People have mentioned that Chase is in on it and we, who are watching the show, are the Schmos. This seems risky since the payoff isn't great and you could alienate people from watching future seasons with such a stunt.
HOWEVER, there's always the chance that Chase KNOWS about them all being actors and has known from the start. But the cast has no idea he knows. Perhaps even the crew doesn't know, besides maybe one or two higher ups.
Consider: At the end of the show they are supposed to pull the curtain back and you get the big "WHAT!!?!?!" from Chase.....but instead, Chase does something incredibly crazy that they can't expect and the entire cast freaks out, only to realize minutes later they have been played.
So, Chase could pretend to have a heart attack when they pull the gotcha, or the cast has something planned where a gun is pulled where they think its full of blanks - but then it goes off and Chase pretends to get hit (blood packets and all) and they all freak out. Then he pulls the gotcha on them and instead of one Schmo with an omg face, you have the entire cast and crew looking silly.
Perhaps one or two people actually know. Maybe Jake and one producer or something.
I really don't think it is the case this season, but it wouldn't be such a bad idea for a future show. I mean, the whole time the crew is freaking out that they will be found out. To turn that all back on them would be pretty awesome.