It looks like you can see something (tail of a plane?) hit just before the explosion...
I think you may be able to make out the tail of the plane, even with the slow frame rate, moving from left to right just visible above the highway prior to the explosion. It's visible in maybe two frames.
It looks like there is something there, but I think it's just traffic on the freeway. ]
Well surely we cant see the plane, the missile or the UFO so we cant make any comment other than, there is no clear plane/missile/UFO there?
I always thought it odd that so few frames of what must have been a heavily videoed environment were released.