The problem is not you getting cancer its the bioaccumulation in things that eat things that die to pesticides. It has a knock on effect that you are not seeing or can account for, and no DEET is not kill crane flies.
you're thinking of other chemicals. DEET doesn't really bioaccumulate, since its a repellent not a pesticide
They might be getting in through the edges of the screen frame, especially it's a shitty aluminum frame that frequently get kinks where bugs could squeeze through because people don't take them out properly. June bugs could absolutely get in through a small gap if it isn't tight in the window frame. But crane flies are also very easy to catch in a cup if you wait for them to land on the wall. I'm not sure if it's when they're near the end of their life span and lethargic but I've scooped some up in my hand and they just sat there until I tossed them outside.
They're all over my house too.
Crane flies creep me out because they look like giant mosquitos (but I'd still rather have them than mosquitos).
