I didn't even remember the fire until after started posting this time, and thinking "why did I consider these guys to deal relevant damage, again?".

No, there isn't much you can do against this mob damage. I've heard it explained as being the accumulated nat-20s of the constituent members, if that helps anything.
That being said, I'm inclined to scrap the damn template and write my own/find a 'brewed substitute. This is creating far too many weird rule interactions lately.