CAA spokesman Khaled al-Alkhyeeri said on Jul 29th the captain and first officer are in good health with very minor injuries. Emergency services reached the aircraft within 35 seconds after touch down using half of their agents within 3 minutes thus efficiently confining the fire to the cargo hold.
I doubt it very much that Fire and Rescue Services in RUH will be able to deploy and be at the site within 35 seconds - unless they already have been waiting there!
Just look at the the way they handled the B737 in April, where the crew declared an emergency right after takeoff and desperately and repeatedly was asking for vectors back to the field. Once they made it safely on the ground, nobody in Riyadh seemed to be in a rush...
My point? They must have known that this incoming airplane was in some sort of trouble.