Wait for the mercenary leader (egzoskeleton) to walk to the middle of the square (point 16). After the conversation, you will be automatically taken to point 15, where the mission will take place and will receive a sniper rifle with ammo (but Gauss also works fine here). Your choice however, doesn't change much, so kill both. You have to choose your target - either take down the client with whom the mercenaries are to meet or their leader. During the conversation, mention the laptop from mission 6 ( Mercenary Camp) of Zaton sector and Uncle Yar from mission 5 ( Kopachy) of Jupiter sector.
Remind the Colonel about the incident with Garry. Target location: points 15, 16 on the map Received from: Kovalsky, after finishing mission 1 and talking with Garry about the mercenaries