Only way this could work is make it a retirement match. Have Cena :ppvbro: Taker's entire career in the face-offs leading up to it, get the neckbeards up into a frenzy, then just as Cena has Mark Mascaras up on his shoulders w a smirk on his face and the crowd is ready to hurl garbage upon them...Taker reverses it, Tombstone, 1-2-3. Taker WINS. CENA retires.
You've got a bigger shock and story than the streak being broken and Broken Down John gets to ride into the sunset. Roman and them are officially thrown into the pool and lets see who can swim.
Best of all you can take it in any direction from there. If Nikki cant trap him after a couple months you can always bring him back in any number of ways. Finally do the heel run. Bring him back face and switch his character up a bit. Or easy transition to that part-time role that you know is eventually coming.
He's been stale for a long time and so has the product. They need more wild card shyt and genuinely unexpected events to shake things up. That's the single biggest thing been missing from the product compared to the old days, more than the risque content even.