Source: The Wrestling Observer Newsletter
As noted, Undertaker was legitimately hospitalized with a severe concussion sustained in his WrestleMania XXX match with Brock Lesnar. Undertaker was released on Monday, however, and was actually backstage at RAW. For whatever reason, the decision was made not to use him on the show.
Those who saw The Undertaker backstage at RAW noted that he was limping around pretty badly, and appeared to be in rough shape.
Regarding the decision to end Undertaker's streak at WrestleMania, there is said to be a number of people in the company who were very unhappy about that decision, but couldn't -- and won't -- say anything about it publicly.
The decision was reportedly made by Vince McMahon, not Undertaker himself. There are conflicting reports regarding the call. Some "in the know" claim that McMahon had to talk Undertaker into it, while others, also "in the know," say McMahon made the call and Undertaker simply went with it. The feeling is that the streak ending would not have happened if 'Taker didn't approve it and he's got that much respect and power backstage.
UPDATE: As previously reported, WWE referee Chad Patton, who served as the in-ring official for the Brock Lesnar vs. Undertaker match at WrestleMania XXX, was not aware that Lesnar was going over in the bout. As noted, he was actually told that Undertaker was supposed to win.
As far as who else in the company knew ahead of time, that is hard to say. We can say for certain that Vince McMahon, Brock Lesnar, Undertaker, Paul Heyman, and likely Triple H and Stephanie McMahon all knew, but beyond that, it's difficult to say.
On the actual script for the show, no finish was listed for the Lesnar-Undertaker match. However, that wasn't unusual, as other matches on the card did not have a finish listed on the script as well. The feeling is that they are trying to prevent talents and agents making money from betting odds.
According to reports, none of the agents who worked the show were aware that The Undertaker was going to lose.
It should be noted, that despite the claim that not many were aware of the finish, enough people, or the right people, must have known. There were two major online betting websites that had Lesnar an unbelievable underdog, nearly 50-to-1 by some odds, that switched to him being an actual betting favorite when the match hit the ring, indicating that a ton of "smart money" came in once the finish was determined and told to whomever was in the loop to know these kind of things.
ORIGINAL: The referee in the Brock Lesnar vs. Undertaker match didn't know the end result. We can confirm that Chad Patton was actually informed ahead of the match that The Undertaker would win, but complied with the rule given to all WWE referees. That rules is that if a wrestler does not kick out, you go ahead and finish with the three count as if it were exactly what was planned.
We can also report that Lesnar privately whispered "thank you" to The Undertaker immediately following the three count to express his gratitude for the honor of breaking the streak. Lesnar and Heyman also went with Vince McMahon to the hospital with 'Taker. We're told Vince was inside the ambulance while Lesnar and Heyman jumped in a vehicle and followed them to the hospital.