This is a still from the first frame showing the rapidly growing light source, which is consistent with an explosion. It appears to be partly shielded, suggesting it may be exploding under and in front of the port wing (the aircraft would be moving from right to left at the moment of impact) perhaps?
Interesting. Not sure if that may just be a lighting artifact between video frames. However, if it is a shadow cast on initial detonation it would not be on the port (left) side since that is in line of sight with the camera and therefore 'under the wing' would be visible, not hidden. The missile appears to approach the aircraft from off centre and to the right. You get a sense for this when you compare the missile track against the post impact aircraft track. So it is more likely the missile approached and detonated on the starboard (right hand) side of the aircraft in which case the initiation of the warhead may have been partly shielded by the fuselage which seems more likely in this case. Not trying to 'make this fit', but this would also support right hand side fragmentation damage alluded to earlier especially the hole punched through the vertical stabilizer from right to left and the (probable) right hand aft engine cowl / tail-cone assembly.
All very sad.