Hi,
If the information you are sending is the same as you stated on your EOI, then there's no real reason why they should reejct you, unless they find something wrong. Also, as soon as you submit your medicals with your ITA, I'm pretty sure it doesnt matter if they expire while in NZIS hands. If they do expire, there's no real cheap alternative, sadly they need to be done again
Anyway, welcome to the forum! I hope your application goes well for you, and if you have any further questions, let us know!