Yeah it probably has to do with the ‘cyclone hides targets’ flag you talked about in your other thread. I wouldn’t be surprised if ‘target unit of ability being cast’ is null entirely or that the location returned when getting it is null. Try printing the xy coordinates of that point or doing something to the player like printing their player number or giving them victory just to see what’s actually being returned.
I still think you should just trigger your own Cyclone so it functions exactly how you want it to.