I haven’t finished reading the thread, but I wonder if this is something other than a camera. I live near woods and a creek and have all sorts of wildlife activity, deer, coyotes, raccoons, etc. We have installed “predator eyes” which turn on a red light at night to make them think that they’ve been spotted. It has been mistaken as a surveillance camera by our neighbors too. I’m not saying that your neighbor isn’t spying on you, but offering that it might be something else.
The only creature of any size would be our cats and we try to get them inside at night. Not always successful. The 10 feet to our property line isn’t going to bring in any animal. If they want to see wildlife, it wouldn’t be on that side of the house. And it’s only one red light.