The name of the mission is a reference to the famous song "Won't Get Fooled Again." The pun is continued further in that the song is by The Who, a four piece band. The mission has you trying to figure out who of these four people is responsible for murder.
While it might be reading too much into it, it's interesting to note that while there are four of them, two of them have pistols rather than each having a different weapon. One carries a rocket launcher, another a sniper rifle, one carries a lighter repeater pistol while the other carries a heavier/slower jakobs revolver. It may have been intentional that these were to represent drums (percussion), singing, lead guitar and bass (which is much slower than the rapid strumming of the lead guitar) respectively.