Sniper Elite Resistance

[robertpbs]

I am looking to gain use of the trench gun (shotgun) but the requirement is to complete the kill mission in Mission 5 Devils Cauldron. I have completed this many times, killing the engineer in the right building according to the map. I have also destroyed the sub and destroyed the 'kleina blumen' production facility and then exfiltrated. At this point the game won't award me the 'star' on the left as I haven't completed all the missions which I gather is not completing the kill challenge. What am I missing here?

[miamew3]

Try asking in that games forum: https://steamcommunity.com/app/2169200/discussions/