ZS-OLD
The aircraft hit the ridge at around 9800', the MSA is 13200'-14200' in the direction they were comming from, impact was more than 3000' below MSA, and that is a fact.
If it broke up in the air, explosion on board or hit my a MANPAD, doing in the vicinity of 150-200 kts, the wreckage would have been strewn over a much larger area not so? if there was a downdraft severe enough to let a 1900 lose a 1000', nevermind 3000' ,there would have been evidence on the ground, a severe microburst leaves a lot of tell tale signs.
I am no expert but witnessed the impala that lost a wing at Lanseria years ago, and that wreckage was spread well over 2 km.
I think the FDR will tell , but it might not be what you want to hear.