Christian Kane and Jensen Ackles actually sang the song they performed. The house band, known as "The Impalas," is made of all Supernatural crew members.
Realizing his friend could really use a break, Lee brought Dean on stage to sing the extremely on-brand Dukes of Hazzard theme "Good Ol' Boys" by Waylon Jennings.
Call of Duty Warzone is a free to play game. It's not on GamePass and it doesn't need Xbox Live Gold either. MW2 and its multiplayer component is not free. You need to buy it if you want to play the single player game or MW2 multiplayer.