Here's another factor: When something is far away from you, it appears to travel slower. For example, the sun is ~150M kilometers away. As the earth rotates through a day, from our perspective it travels ~942M kilometers, meaning it appears to be traveling at 40 million kph through the sky. However, it's just sitting there in one spot.
If I make a wild-ass guess that the fireball was visible over a trajectory of about 100,000 feet, that's about 30 km.
At 11 km/s, then, it should appear for around 3 seconds.
I rewatched the video, which is 5 seconds in all, and it looks to me like the light is pretty close to three seconds long.
Aside from that, sure, it could've been slowed down, and could be at an angle, so it may all be a coincidence.