I'm not sure about hospital policy etc. but a friend of mine was given three possible dates due to a very irregular cycle etc and they waited until she was overdue on the 3rd date before discussing induction and her dates were 2 weeks apart!
If you are well and your bub is well then I would think you could say no to induction, maybe explain to your midwife about your dates etc. and see how you go and explain your reasons for not wanting to be induced.
it is your baby, your body so you should have the decision.
Good luck with it all who knows your bub might decide to enter the world before your appt! You never know xxx