Kaoms Cache Unique chest totem damage to minions

Reference:
https://pathofexile.gamepedia.com/Kaom%27s_Cache

That totem of this unique strongbox probably does not have the "reduced damage to minions" properly set. It is so far the ONLY thing in the whole game that managed to wipe all my minions with one spell, including both spectres and my guardian (that hurts the most).

Those guys survived Uber Elder, Uber Atziri and everything in Delve, seeing them fall all in one spell feel more like a bug to me. Please investigate, perhaps turn on the minion damage koeficient?