It doesn’t work the way you think, otherwise it would be a must have skill in any build. Ulzuin’s Wrath is a side effect of Vindictive Flame: if Vindictive Flame is triggered and there’re ranged enemies in Ulzuin’s Wrath’s area of effect, they will take damage.
Also converted VF’s/UW’s damage is now affected by armor, so you will have to try very hard to increase the damage to decent values, and UW’s dmg can only be increased by retaliation damage.