The current itself, although huge, travels in a conduit that is very small. What in principle could affect the camera is the associated magnetic field that surrounds any electrical conduit, even a lightning bolt. A rapidly fluctuating magnetic field can induce currents in other electrical components (this is how an EMP burst works). It's distance dependent and I'm not sure how susceptible a digital CCD camera would be to this in this case - and most especially if it would cause an effect noticeable in the video - a camera like this don't have much of a frame rate, so any glithching could have happened between frames after all.
At any rate, I don't think the lack of noticeable "glitch" necessarily mean much, imo.
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Griatch