Most likely the "black boxes" are not going to show a thing except normal ops until they suddenly stop, when the tail was blow off by the missile.
The FDR will yield an exact position where power was lost from the tail being severed shortly after detonation. From that position it will be possible to determine the area where the launcher could be located. Shrapnel marks will provide information on missile aspect which may be used to derive the missile vector back to the launch site.