It’s highly recommended to get full medical and evacuation insurance, and travel insurance that covers petty theft, loss and equipment damage. Theft is very unlikely, but it’ll give you peace of mind. Heat, bumps and dust are always an issue for cameras and sensitive electronics, and Namibia has all three in abundance.
With regards to personal injury, road accidents are the biggest risk. Accidents can happen in very remote areas so make sure your policy covers helicopter and other emergency evacuation services. It’s also a very good idea to take the best vehicle insurance available. Major damage to a 4x4 can be very expensive, but loose gravel can also chip paintwork and windscreens so make sure you’re covered.