AOE= Area of Effect, referring to an ability that hits a targeted area instead of a specific target.

If this is still happening for some, I just thought I'd throw out what i got to work after getting absolutely no where for quite a while. Once you get a round to spawn, get them next to where one of the next droids will spawn and be ready to AOE one when it has FULLY left the container but isn't target-able. Tried this when it first pops up but only worked when they had stepped out. It got me passed the glitch after only a few tries, where as I had tried all other suggestions and just waiting through spawns for about an hour. Hope this helps someone, was getting thoroughly irritated myself with this.