Too many coincidences
There is some disagreement here whether the video is genuine or not.
Consider this however.
The video clearly shows an explosion around the aft fuselage of the aircraft. There is too much smoke for a simple bomb - there must have been substantial combustion. Furthermore the wings and everything forward remained intact. And the plane kept flying relatively unaffected for at least some time.
This video was released within 24 hours of the crash, before non-involved parties could have known any details. There was no claim of a missile - that seems to have been assumed in early reports. There was just a claim of "brought down" or "bring down."
Our current understanding of the crash is an explosion in the aft fuselage. In a plane with an aft centre tank. And the plane appears to have flown on on for some distance. And the wings and the forward fuselage appear to have come down relatively in one piece.
People have speculated it is the wrong aircraft and the combustion was an engine fire on a DC9 or similar (i.e. rear mounted engines). Would not the sudden loss of an engine cause significant yaw?
Plus no one has been able to find another source of this footage.
Sometimes 2+2 does equal 4