When I use FXNecroSkeletonPriest.Play(Game.GetPlayer(), -1) the effect plays at the players feet and not at chest level where I want it to. The effect works fine on the necro skeletons, but it is almost like it doesn't know where to "attach" to on other actors. Can anyone help me make sense of this issue?

Well, the local origin of the player's skeleton is at the feet. I suspect that the local origin of the necro skeletons are at their chest. The game returns coordinates of an object by looking at the position of an object's local origin.

Is it possible then to play the visual effect with some sort of Z offset from the player? Or maybe create an invisible activator at some Z offset from the player and then play the effect on the activator instead? How would one go about making it so that the activator is "attached" to the player so that when the player moves, the activator moves as well?