GUYS I figured out the "big surprise"
Kendrick gave one clue about the Super Bowl performance- "Storytelling." Rumors of a "big surprise" have been going around, as well.
Way back, Kendrick did an interview on a French radio station after the release of GKMC where the host brought up a tweet by Pharrell calling him the "Bob Dylan of his generation." Kendrick commented that the thing that connected them was "storytelling." AFAIK this was the first and only time Kendrick mentioned Bob Dylan in an interview.
UNTIL TODAY. Timmy and Kenny had a brief conversation, and within those 6 minutes and 28 seconds, Bob Dylan was brought up.
So, if my calculations are correct...
BOB DYLAN CONFIRMED GUEST AT SUPER BOWL. KENDRICK LAMAR WILL BE RAPPING SUBTERRANEAN HOMESICK BLUES AND DYLAN WILL BE DOING A FOLK ROCK PERFORMANCE OF MEET THE GRAHAMS WITH A 2 MINUTE LONG HARMONICA SOLO