This would be the perfect way to screw Daniel Bryan and further build to Bryan/HHH at Wrestlemania.
Say Christian is found attacked off-screen about twenty or thirty minutes before the chamber match is to start. Triple H then states right before the match that unfortunately, it's too late to find a proper replacement and so the match is to go on as a five man match instead. So the match happens and then Daniel Bryan pins Orton at the end to become the new WWE World Heavyweight Champion but his celebration is cut short yet again when Triple H (or Kane perhaps, but it works better with HHH since it's supposed to build to HHH/Bryan) comes out and says that the match isn't over because while the match was still going on, he just happened to have found a sixth person and if Bryan wants to walk out as champion, he must go through one more man. And this person ends up pinning Bryan to become champion since Bryan is much too weak to go through a completely fresh competitor after having already lasted through an entire chamber match (also keeping in mind that Bryan is coming into the match with pre-sustained injuries already.) The problem is, the only person who could fill this role is Brock Lesnar (who would be revealed as Christian's assailant), and what a poor way to get the title on Brock that would be. If he were gonna win the title, then he should have just booked him in the chamber match to begin with. Either way, it could lead to Bryan/HHH and Batista/Lesnar for the strap should they choose to go down this route (which they won't.)