I had to give it a few tries as well; it's definitely challenging (a welcome sort of challenge!) but you CAN do it! Make sure to zoom out as far as you can to widen your view, and keep in mind that 1) your ability can take out orbs in a small area, so try to get as many as you can at a time, and 2) your NPC helper will (mostly) handle the orbs in their direct path. It may be helpful to assign your duty ability to a keybind to make it easier to trigger. (I'd often miss clicking the darned thing.)