Exec, you came close, but it's neither one of them. You got two good mission there mate, but the Dead by Dawn mission is an airstrike mission and not artillery, and the FO's Lament mission won't work since I can't get hold of the "STT scoped weapons pack".
Anyways, i appreciate your effort in helping me to find the mission.
damn... should have kept it in the missions folder in the first place!