I would probably restart week 6 if it was me. And don't have too longer break or you'll lose your momentum completely.
For what it's worth - I ran C25K every day. Indeed in the early, easier week I sometime ran twice a day.
I continued running daily upon finishing C25K, progressing to 35 min runs, 40 minute runs, then a daily 5k run and even through to 10k runs. I run every day.
Since the beginning of April, so coming up to 4 months, there have been only 3 or 4 days I've not run.
I have a school friend (Facebook friend) who runs a gym with her husband and they are both personal trainers. Therefore uber fit. They think nothing of a 5k run. Indeed they often use a 5k run as a warmup to exercise. ie not even the actual exercise, just preparing the body for proper exercise to do afterwards.
I take this mindset in my running. Fit and healthy people can run 5Ks as though it's just an everyday part of their day, not even exercise. I suppose the same way I used to view the 1.5k walk to school and back twice a had - healthy but not actually exercise.
This mindset in itself makes me think that as long as you're not constantly pushing yourself faster and faster and are not increasing up to frequent high (10k +) distances, that a daily 5k run (ie every day) is a healthy and very good thing to add to your day if you have the time.
So I respectfully disagree with your husband. 
I'm sure the NHS advises 30 minutes of high heart-rate exercise every day. A 5K run takes me 32-34 minutes, so I think unless I'm doing other cardiovascular exercise in the day, that a 5K run every day is a good thing.
The only important thing, I think, is good training on things like foot placement when running to avoid foot/leg aches. Shoulder, arm and head positioning without tension to avoid upper body aches. Well fitting shoes and adequate warm up and cool down. All that in place and not pushing yourself to go fast and I think daily running isn't a problem if you have the time.