Horses do tend to want to follow, especially if they sense their rider is more of a passenger. My pony is always the leader, IF I'm on her. With beginners though she refuses to lead. She was my first horse and she used to refuse to lead with me, now she actually wants to. I think it's just because she doesn't feel confident the same way with a beginner.
It's possible your horses just don't see your husband as a fearless, trustworthy leader yet and that's why they don't want to lead if you aren't riding them.