
First of all, fact is some bitches find it difficult to make the adjustment from being a pet, to being a mum. Sounds like she may be one of those (in which case get her through doing this litter and get her spayed!). I had one who refused to pooh her litter - pee, fine but not the other with the result that the poor little mites were pretty uncomfortable early days - despite my best efforts! She was one who hadn't totally settled to her job either - she'd tolerate going in to feed them when they shouted, but wanted out pretty much as soon as they started falling off the teats and going back to sleep. Once outside the box, she'd stand there and mimble at them - waking them all up. It was HARD WORK. And yes, that was her first and last litter, even if her puppies were good enough for me to keep two.
Provided she tops the puppies up before leaving, and they have independent heating, she can go for a walk - provided you use a diluted disinfectant wipe for feet and teats before letting her back in with them. It might do her good actually.
I'd suggest that provided she does attend to them, every 2 hours or prior shouting to be fed, you don't have to make her stay in with them - and also re the extra heating when she's not in there as newborn puppies can't regulate their own temperature.
I'd get your husband to 'withdraw' now before he has to go back to work.