This page of the Far Cry 6 game guide contains a walkthrough of the operation Precious Cargo - one of the main missions in Valle De Oro. The following walkthrough explains, among other things, where to find Rafael, how to free the detained refugees and how to get them to the port in time.
You can take this mission after completing operation Balance the Books and Bembe is the quest-giver once again.
From Bembe, you will receive a picture of Rafael, the man you need to meet up with. You need to reach the Azucar plantation, where you will learn that your allies need to be rescued.
Free Rafael and the refugees
There are enemy soldiers in the plantation area. The recommended tactic is to eliminate them with sneak attacks, but even if you alert enemies, you won't have to worry about hostages being killed. Pay particular attention to the tower where the sniper may have set up.
It's best to start freeing the rebels only after you've at least partially secured the area - walk up to the refugees and hold down the interaction button to free them one by one. You also need to talk to Rafael.
Deliver the refugees to Bembe
You need to reach the large garage where the truck intended to transport the refugees is parked.
The game will start a timer and you will have 2 and a half minutes to reach your destination, but you don't have to stress too much. Mark the port on the world map to have the radar's GPS show you where to turn (blue line). Stay on the main asphalt roads so you don't get stuck by driving into a ditch, for example. Also, avoid colliding with soldiers or military vehicles along the way.
When you reach the port gate, a short cut-scene will play showing the conversation with the guard and the game will stop counting down. Head out to the end of the dock while avoiding colliding with potential environmental elements and people along the way.
Another cut-scene will play when you deliver the refugees to Bembe and the operation will be complete.