At your stage in post transplant, I say , "Go for it!"
I have a small travel size Lysol spray that I take in my suitcase. It comes in handy when I feel the need for extra safety.
Depending on the situation (an extended stay), I have been known to take a hand sanitizer with the pump dispenser, and kept it in a convenient place in the our motel room.
I encourage your husband to also carry his own sanitizer. Men are so lucky to have pockets in their pants!!!
And of course, take the meds on schedule - a pocket pill box and a bottle of water if you are on the road!

Jodee, Did you get a packet of information from the transplant dept when you were discharged? I think that there is a section about travel in it. I will hunt for mine after while and see what I find. In the meantime, I look forward to hearing from our other members:-)