Three’s Company

Head to the overlook Olivo Moro and equip the sniper rifle there. Start taking out the enemy vehicles then destroy the remaining reinforcements. Once done, head to the next overlook then shoot the control box by the guard house.

After the cutscene, provide covering fire to Annika and Teo. If your ammo runs out, you can glide towards them and escort them to their chopper. Before latching to the chopper, make sure to change your sniper rifle to a grenade launcher from one of the nearby weapon racks. Tether yourself on the chopper and provide covering fire as you make your escape. Later on, another enemy helicopter will appear. Grapple to that chopper and hijack it then take out the remaining enemies to complete the mission.