Head north-west along a very linear path. You don't need to look around for collectibles anymore, you should have already emptied Shantytown during your previous visit. Slide down the zip-line and use the nearby rope bridge.
When you reach the platform you have already used before, turn slightly to the left and stop at the edge. Wait until the gondola stops in front of you and jump over to it when the time is right (screenshot). The gondola will take you to a new location within Gondola Transport, and you'll listen to some new conversations on the way (reward: 100 XP).