Partial Source: The Wrestling Observer Newsletter
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.