I don't see why not. If it is in good working order and you know how to correctly operate it, it should be no more risky than any other stove.
Enders petrol stoves were original equipment in the earlier VW campers.
Sure, if you can guarantee that all the valves are in top condition, and the metal construction has no faults. But even stovies won't give you that guarantee! And if something goes wrong with a petrol/naptha stove, the results are usually very unpleasant. Outdoors, the risk is less. IN a van? Rather you than me!