I don't think we can hold much store on what normally happens in NHS maternity.
Let's not forget she went to a zika virus risk area. Presumably it was risk assessed and all risks could be mitigated.
Similarly, it's not difficult to assume that the risks of being overdue can be similarly mitigated if you have enough resources.
An in-house scanner, foetal heart monitor and doctor/midwife available 24 hours a day. Pop onto the monitor for half an hour multiple times per day, whilewatching tv and being scanned, and it could be risk assessed that any potential danger could be caught within time for emergency actions.
I refused induction for DC3, born naturally 40+16. If Meghan is similarly as against induction as I was, there are ways she it can be made as safe as possible to do so.