Here's what I got out pof the final segment.
Cena saying he didn't win the big one,means he doesn't have that one major victory in a feud that will define his career.
Rock had Austin at Mania, Cena doesn't really have that career defining feud.
Also, both are breaking character at times and say things out of character, and it is meant to produce more interest, Because people in our circles are the wasiest people to work.