Some enemy AI's seem frozen in place when invisible on exterminate missions

[CaptainJLP]

I don't know i was just doing a exterminate on sedna for focus, I was using noise arrows enemies were not even moving towards it, only some, but all the other ones seemed frozen so i hugged up against them, they still didn't move, they became alerted, but still didn't make one movement, just kept looking at the walls. I have no clue what has caused this behavior. I do have max power range excluding new set mods (if they even include power range) and all they do is look at the wall.

NOTE that in the time i was doing this i was using cloak (invisibility).