[Caryatis]

The spells_new DB field "effect_limit_valueX" is the proc modifier for these spells.

and you are correct they only proc when dmg is dealt:

if (damage > 0)
	{
		// Give the opportunity to throw back a defensive proc, if we are successful in affecting damage on our target
		other->TriggerDefensiveProcs(this);
		
        return true;
	}