Gersh Dolls - Get a Gersh Device. Go to the pack-a-punch room and on the left side, on a pipe under the ground there will be a doll on it that you have to throw a gersh device at. Go to the balcony at the top of the Widow’s Wine lander and throw a gersh device at the doll above the wall with a big star on it, which will have a doll on the railing above it and make sure the gersh device stays up there. Go to Stamin-Up and not too far in front of it, in the air there is a walkway up there which will have a doll on one end and you will have to land the gersh device on up there.
Dolls - go to the other side of the KN-44 wall-buy and the ground there will be fire and to the right of it will be a doll in the ground to interact with. Now it will spawn in dolls around the map and they will be in different places every time. The first spawn is on top of the rubble next to the Kuda Wall-buy. The next spawn is on a canister next to a turret and the perk-a-cola machine. The next spawn is on the walkway from before in front of Stamin-Up. The next spawn is in front of a big generator next to the water in the Stamin-Up lander room. The final spawn is on top of that previous generator. Now that you have all 5 dolls, go back to the fire behind the KN-44 and interact with the doll again and it will start playing the music.