This doesn't answer your question but soul shatter requires that you slot a soul magic skill for it to fire. I don't even bother putting points into it since I never slot those skills.
MrTarkanian48 wrote: »This doesn't answer your question but soul shatter requires that you slot a soul magic skill for it to fire. I don't even bother putting points into it since I never slot those skills.
I am pretty sure the OP refers to "Shatter Soul" the morph of the Soul Strike Ultimate, and not "Soul Shatter" the passive.
That being said, I have not tested it, but I would assume that if you are wearing 5 pc. VD, and use Shatter Soul on a low health enemy and kill him, any enemies near the one you kill would be hit with both the AOE explosion from Shatter Soul and the Vicious Death explosion. I cannot think of any reason that one would cancel out the other.