This achievement glitches or something?

Trying to get the side arm savant badge in the campaign. It says complete night raid using only pistols, knives and gadgets. I went through used a knife, pistol then and when I got an RPG along with a nade launcher I used them becuase they are gadgets. The RPG is needed for the heli at the end anyways. I am confused as to where is am fucking up? Am I not allowed to use squad commands to help, am I now supposed to use the RPG on people?