According to the people in your video, they live only 3 miles away from the airport. I suspect the noise they were listening to was that of an airliner(s) waiting for take off until the end when it decided to shut off the engines.
The corresponding flash was probably just a coincidental flash of lightening, probably an off shore or inland storm......that's the best I can come up with...
I would think if you had lived by an airport for any length of time you would be familiar with many sounds and know when you were hearing something out of the ordinary even for that location.
I lived the first 18 years of my life less than three miles from Stapleton Int. Airport and not even when planes were landing or taking off within a quarter mile of my house was the volume of the sound that loud nor did it sound like that. It didn’t sound anything like an airplane to me either. We also became so inured to the sound of air traffic that we rarely noticed it much less thought it was strange or out of place.