Head to the far off province of Soros to start this mission. After the cutscene, approach Mario for another cutscene. You’ll have to head to Vigilator Nord and meet up with Dimah’s contact. After the scene, you have to complete the encounter by tethering the grounded boat to the water and reeling it in.
After the encounter, open your Commlink and fast-travel to Manaea as instructed. Once there, jump off from the chopper to complete the mission. You can now fast-travel to any map marker at a cost of one flare. Fast-traveling to liberated provinces is free and will consume no flares.