Helicopter was my first thought as well, possibly an aeromedical type helicopter that responds to accident scenes. I've never looked at one of those close up, but when I've seen news video of them responding to accidents, they seem to have more lights, including really bright strobes, on them than a standard helo.
Helicopters are very noisy and can be heard from a long ways off, you'd think Barone would have heard a helicopter as it got closer to him. If that's the case, is the guy stupid or purposely not mentioning it? Which leads me back to Knapp's dismissive comments about this sighting last week, and the fact he's not interviewed Barone.