I would consider mounting a camera (s) on the fence itself angled looking down the sidewalk or maybe just inside the fence out of reach. I would think a turret on the fence post painted the color of the fence would go fairly unnoticed - my neighbor did that and nobody sees it. I will see if he still has a before and after screenshot showing the difference it made - the picture was a pixelated mess when he zoomed in over the fence - even though the fence wasn't in view, so much IR was lost on the fence that once zoomed in, you couldn't make out anything of the person on the sidewalk.
Any camera on the house with some zoom will probably suffer from the IR bounce off the fence once you zoom in PLUS the person on the other side of the fence will not be completely illuminated by the IR as the fence is going to block a lot of IR from getting to the subject. You can see just from your camera how much of the fence is being hit with IR which means a lot of it is not getting to the other side of the fence. Or add an external
IR illuminator on the other side of the fence.
Plus, once it is known you have cameras, they will just duck and be below the fence and then you don't get them at all.