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?
Aradin does not care for children - or druids, for that matter. All he cares about is himself and - to an extent - his minions. Goblins who are busy murdering children are Goblins who are NOT fighting and/or chasing him and his crew.
As to Aradin and his crew - at least one adventurer's guild rejected Remira for being "too renumeration focused/motivated" ...
