Revenge is a Dish Best Eaten

Saw this at Bronte's mansion. The in-game harp has some differences, but in both scenarios a shooting takes place near it.

Hey y'all! Its me, back after some family trouble.

Anyway, I just finished the mission "Revenge is a dish best eaten" and noticed everyone at camp is gone, exept for Lenny, Javier, Dutch,Hosea, Uncle and Cain, but I don't think he counts.

Is this part of the game or a bug?