The two images in the video are very different. If what the people saw looked anything like the dark shape in one of the pictures, I don't blame them for being afraid. I look at the sky all the time and have never seen anything like that! I think it might have been photoshopped?
It looks like a wacky arm waving inflatable tube man to me... And in the upper photo, it actually appears to be moving away from the direction of the wind as indicated by the other clouds. Seems fishy.