With regards to this image and the dark figured person, upon seeing the enhanced images (I'm afraid I can't locate them but will add asap), i actually think this could actually be Corrie. My reasoning for this is that the CCTV camera is indoors, and with it being night time, it is using Infrared in order to capture images in the dark. This can give an off representation of colours at the best of times, but when an infrared camera is filming though a pane of glass, with a white frame, a lot of the lighter colour will be shown around the window frame, making images outside appear darker. When the image was altered and made lighter, i think the outfit looks very similar to the one corrie was wearing, and the subject is holding something in "his" left hand, just like corrie was when he was eating his food.
Edit to add my adjustment of the photo to brighten things up - If you look at the top of the persons head, it looks in my opinion as if they have short hair (male?) and light is reflecting off the ends at the top.
I have 4 CCTV cameras on the outside of my house, and whilst i was waiting for one to be mounted on the wall outside, i had it inside recording through the window, and everything appeared very dark due to the problems I mentioned above. I'm afraid i'm not a very technical person but I hope i've explained my reasoning for my opinion well enough!
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