No Witnesses: Don't leave any witnesses alive in Paez's HQ challenge.
I've been thru this mission 2 times (recruit & vet) and I thought I cleaned out every baddy in Paez's HQ, even the rifleman in the tower on the left. Then I mopped up the guys standing in the middle and proceeded to take Paez to safety.
But - I didn't get the cheevo!!
Who did I miss, where is he?