I'm surprised the doctor let him go back to work so soon considering the difficulty with transportation. I broke my right leg and couldn't drive. I broke my left leg and couldn't drive because my truck has a clutch. After my bones healed, I had to do physical therapy to strengthen my muscles and tendons and kind of re-learn how to properly put weight on my legs.
My doctor put me on short term disability because it was absolutely unrealistic for me to try to use public transportation on crutches, not to mention the fact that I was supposed to be keeping my legs elevated as much as possible to combat the swelling.
I'm not a doctor by any means, but it would seem to me your husband has tried to go back to work too soon. Using crutches can be excruciatingly painful in the first month or so. It kills the palms of my hands and being boney, I get terrible bruises under my arms along my ribs. My good leg gets so sore and tired. It's rough!
I think your husband should talk to his doctor and let them know how difficult it's been for him to get to work. Ask the doctor's advice about alternatives to crutches. Your insurance may pay for it if it's deemed medically necessary. Where I live, you can rent medical equipment which is really nice because then you aren't stuck with something that you may never ever need again.
Bless your husband for wanting to get back to work so soon, but he really needs to be thinking about healing properly or he could have problems with that ankle for the rest of his life.
Just my opinion and best wishes.