Neighbors threw cat outside in -10f weather

Pic is while I'm typing this. My neighbors have had mainly outdoor cat this summer, and it seemed to transition to indoor outdoor as it got cooler. I've become close friends with her, letting her inside, pets, treats, but always made sure she went back home. I was surprised to see her on my porch tonight in the freezing weather, snow on the ground. I let her in and she doesn't want to leave, can't blame her.

I looked at my security camera and it's hard to tell, just a few pixels zoomed in, but it seems like the door opened, cat flew out, and she kind of sat there stunned for a moment before walking over to my house.

I'm definitely keeping her in tonight, and it's going to be freezing tomorrow. She is the sweetest thing. I don't want to steal someone's cat and I don't want to confront my neighbors.