This was shot in the wintertime because the north pole (think Polaris) is bathed in sunlight much of the time and there is a noticeable glow to the north.
If I understand the gist of your post, I'm afraid that your idea is physically impossible. Any glow seen toward the north, whether winter or summer, must originate with the source usually less than 100 miles distant from the observer. Regardless, the North Pole is in perpetual darkness during Northern Hemisphere midwinter.
Well then we agree to disagree.
This has been studied both analytically and with measurements; there's no room for disagreement.
BrooksObs is correct that artificial light pollution has only a modest effect 100 miles from the source, and no measurable effect 200 miles from the source. This was explored decades ago in a classic paper by R. H. Garstang.
The Sun, being much brighter than any artificial light pollution, and illuminating the atmosphere top down rather than bottom up, is visible from greater distances. The classic definition of astronomical twilight states that the glow of sunlight disappears when the Sun is 18 degrees below the horizon. That means that the closest spot in direct sunlight is 18 * 60 nautical miles away, which is 1,243 statute miles. That's a long way, but nowhere near the distance from Pennsylvania to the arctic.
So any glow to the north around midnight in summer around latitude 40N is not due to diffused sunlight. It might be due to artificial light pollution, airglow, or the aurora.