There's a better, longer video on Reddit. At the beginning of the video, it sounds like the Ram Air Turbine (RAT) is deployed, which would suggest a dual engine failure.
I'm assuming the Ram Air Turbine gives extra evidence of a dual engine failure (or at least the engine that generated power). Engine spools down, power is lost, air turbine needs to be deployed.
Those things are tiny and very transparent (since it's pretty much a propeller) and video compression, plus it's a video of a screen, will eat it up against a clear sky.
