So... she's nano-tech. When she fires a shot, her shields are down. Right moment to strike. As for the mute... really? Your that stubborn and belligerent NOT to live? She has friends that need her to live... but the way of Sex can't be forced too much here.
Anyone getting Thanos flashbacks here, anyone. I am expecting next chapter the witch is going to say you should've gone for the head and to just fire a spell at point blank that won't miss.