But i have a feeling it will just lead to Vince booking some kinda tag match. And then dropping off tv again.
CM Punk and Alberto Del Rio vs Ryback and Sheamus - or something yawn inducing, to that effect.
See if I were in Vinnie Mac's shoes, I'd want to implement a gamechanger or two. Let's assume that John Cena should be able to compete at HIAC, but they are going to run with the backup plan. So tonight, Cena comes out and delivers one of his usual promos, stating that his recovery is taking longer than he expected and therefore, he won't be able to compete at HIAC. Punk comes out, cuts one of his promos on Cena, until Vince McMahon interrupts.
Vince comes out and talks about the history and the proud tradition of the WWE Championship before mentioning something about making a few changes. Vince signals to the back and out comes a couple of suits carrying a briefcase. Inside that briefcase is the new title belt which Vince reveals to everybody and then presents to CM Punk. It's a very pompous affair, in which the crowd will no doubt boo. Vince will then say:
"...However, since John Cena is unable to compete at Hell In A Cell, I've taken the liberty in selecting a new opponent for CM Punk".
At which point, the new opponent (use your imagination, could be Ryback, Ziggler, Vince McMahon himself, or even Undertaker) comes out and hits the ring. Cena walks out, not to be seen until after the conclusion of HIAC...Or so we think.
At HIAC, the new opponent seems to have Punk's number, until Punk takes control of the match through malicious means. Then the "big surprise" - Cena runs in to try and assist the new opponent, but the new opponent decks Cena for trying to interfere. Punk then slaps on the Anaconda Vice or hits the GTS (if it's Ziggler or Vinnie Mac), or gets a rollup (if it's Ryback or Undertaker) and takes the victory.
After the match, Cena tries to reason with the new opponent, but they are having none of it, so Cena decks him and then Punk, before taking the WWE Championship, and walking out of the arena (to a chorus of boos) to close the show.
From here on, they can run with a Cena heel turn, or abort it and justify his actions as a result of frustration for trying to do the right thing. He'll then redeem himself by beating Punk at Survivor Series for the WWE Championship. CM Punk will then regain the WWE Championship in the TLC rematch - just in time to face The Rock at Royal Rumble.