The tieflings are refugees who have nowhere else to go. They are families and children. Aradin and his gang are adventurers who chose to get into a fight with goblins at their own camp and then led those goblins back to the grove full of refugees.
And no, of course I wouldn't lead an army to a refugee camp. Certainly not when I'm the one who is entirely at fault for the confrontation to begin with. Why should children die because I'm an idiot?
