Anyone know about [Chaos Golem of the Maelström] withered stack?

Maelström golem's quality effect [Minions have n% increased Effect of Withered]
It was quit powerful with Ashes of the Stars + enhance support
But I don't know how many withered stacked with one golem

According to wiki
Damage from multiple auras does not stack, but each can apply stacks of withered.

In my experience, I need 2 golems for 15 withered stack

Does anyone know exactly?