My understanding with the drones is that the FAA controls the air space, not private land owners. As long as the drone was not flown over groups of people and they pilot maintained line of sight, they should be fine. Since the park is closed, I do not think they broke the people rule. The line of sight is questionable in this video. Also, Kings Dominion is in a Class G airspace so there is no need to contact the ATC. I would not encourage people to push these rules and cause an accident. If an accident would occur, the pilot in question would be fully liable, even in the event of a "run away".
Here are the guidelines from the FAA's website:
Fly at or below 400 feet
Keep your UAS within sight
Never fly near other aircraft, especially near airports
Never fly over groups of people
Never fly over stadiums or sports events
Never fly near emergency response efforts such as fires
Never fly under the influence
Be aware of airspace requirements