1) did any of the other aircraft on the route of flight report severe turbulence? (there would have been a string of aircraft from Brazil to Europe that night).
2) WX Radar only shows precipitation and not turbulence.
3) No crew in their right mind would fly into severe turbulence if they knew it was there.
4) I was booked onto that plane a week from now. When I found out I was booked Air France a few days ago, I changed my ticket to another airline due to past experiences with flying Air France from CDG to Rio. Once it took 48 hrs to get to Rio due to technical problems.....(complete blackout as the aeroplane taxied out onto the runway late one foggy night - 5 "tries" later the passengers rebelled and refused to fly on the aeroplane - was a different aeroplane make and model so unconnected with this incident).