Might as well throw my hat into the ring here.

From what I heard, Brock has 7 or 8 matches left on his contract, but that is just rumored. There's been talk of adding more matches to his contract and there has been talk of Brock leaving after a match with Sting, then setting up for feud with Sting/Cena or Sting/Wyatt depending whether or not Sting comes in heel or face.

Not sure what Cena got for the match, but I'm guessing the usual amount of pay and maybe one of the guys backstage gave him a talking to for poor performance. With how the Cena and Lesnar match was, I wouldn't be surprised if the finish was planned hours before the event. The whole match just looked sloppy to me.