If you mean the one where you have to conquer all control points to have them green, it is doable. It is easier to do it in group as you can parallelize attacks, but solo is definitely doable. It's just tedious and takes long time.
Couple of tips: do it when you have invaded map, because when there's invasion, occupying forces don't send attack squads in those regions. Always check the map and prioritize red pistols - you have to eliminate them ASAP. And call somebody to help you with it, the'll appreciate trophy as well![]()