There is the possibility it was an accident - noone took responsibility for this, and you know Moslems LOVE to say they did it!
As to the appearance of being a rocket/missile going up, I saw a good show on this that somewhat put my fears to rest. Can’t remember which show it was, been a while and there are several disaster shows I love to watch, but basically it came down to the plane breaking apart then the bulk of the body lifting sharply upward in flame, appearing possibly straight up at some angles.
It was truly sad, either way. Lots of people may’ve been left alive in that horror of facing up to the sky (no cockpit) then falling down backward/etc.
There were victims with water in their lungs - meaning they technically drowned. They probably drowned after breaking every bone in their body once they hit the water.