Other generals can have balloons also. Check out my vid https://www.youtube.com/watch?v=cPx5nGXWgP8 , another one of my generals was being followed by the hot air balloonist. His rank was 9 stars- 1 more than Napoleon. If your general gains enough experience, he can be followed by the hot air balloonist, but it takes a long time. My other general got the hot air balloon after like 150 turns.