The only way to proc the Thriving Survivor armor set bonus opening act with suspend grenades is if the suspend grenade kills then with the initial damage. Does not proc if the damage over time for Deimosuffusion kills them, if you kill them with a gun while they are under the suspend effect from the grenade, or if you kill an enemy while you have weaver's trance active and then kill the suspended enemy while they are under then effect of the suspend. I do not know if this is functioning as you intended or if there is something wrong here. I have been under the impression that if you kill an enemy with they are suspended from a suspend grenade it counts as a grenade kill. But it is not working for the Thriving Survivor armor set bonus opening act.