When Lesnar and Reigns knew of Wrestlemania outcome
The Wrestling Observer is reporting that Brock Lesnar knew he was set to lose the WWE title to Seth Rollins before he signed his new contract, so the creative side of things did not really play a big part in his decision.
Reigns is said to have been told at a later stage than Lesnar, but he was well aware that plans were open to changing. None of the other wrestlers knew what was going down until the day itself. It’s not clear when Rollins was told.
There is said to be a bit of bitterness backstage among talent and management who feel building Reigns up for a year and not giving him the win was a bad decision, inspite of the negative fan reaction.