Why would anyone ever believe that Botswana is capable of investigating an aircraft accident? Does the Botswana Department of Transportation and Communication have a handful of trained and experienced investigators lounging in a back room eagerly waiting to crack their next case? If they did find the motivation to launch an investigation would anyone find the results credible?
Pilots have excluded almost nearly any possibility other than a mechanical one for the accident.
The only possibility that people on this site have almost nearly raised is that the aircraft was flown overweight.
Unfortunately I don't think there is any chance that we will find out what brought that plane down. I have equally little faith in the investigative powers of the Botswanan Government and the anonymous posters on PPruNe. That is a real shame for the relatives of the pilot and the passengers killed in this crash, not to mention for the hundreds of caravan pilots flying in similar conditions who would love to know exactly how to avoid this ever happening to them. But it is the reality of living and working in this part of the world, so I am happier to accept that I'm not going to get any answers than to try to stretch the circumstances of this crash to implicate a pilot who isn't going to have the opportunity to speak for himself.