I think the dark coloring and lack of clear chain patterning is an effect of the dark colored waters the fish is from. I see chain pickerel colored that way in several of the waters that are dark like Richmond Mill is. Northern pike also tend to have substantial patterning in their fins, this fish doesn't... Plus, I would be highly surprised a northern pike would be stocked into a Piedmont impoundment in southern NC. Anything is possible though. I have never seen a chain pickerelxnorthern pike hybrid so I can't say what one would look like.