Whatever happens at the Ambulence match will be dissapointing. Yes, not exciting but dissapointing.
1) If the match ends in a tie by some reason. - Boring, repeat of Royal Rumble. Dissapointment.
2)If Kane wins - It would be very weird, because after that PPV is Wrestlemania, in which John Cena is supposed to face Rock. Its supposed to be a icon vs icon match, a clash of generations, like the rock vs hulk hogan mathces were, its supposed to be main attraction of wrestlemania. So by making Cena loose, just before Royal Rumble, the match will loose much of the attraction. Cena needs to be the unbeatable Superman that he was before he faces Rock, thats the only way the match can have serious attraction.
3)If Cena wins - WWE will and should probably make him win, to give him a lift before Wrestlemania. But then again Kane's image will take a huge knock. Why bring Kane back with his mask and shit as a monstar, if u r gonna make him loose in a big match like this just after 2 months of his return. For all the hype, wwe has yet to make him win a match officially since his return. Loosing against cena, might just turn him into the boring thing he became after removing his mask.