Hi Jennifer!
Thank you for visiting the Moms Panel!
You will have a wonderful dining experience at
Cinderella's Royal Table!
I think it is probably unlikely that your dinner will be finished within an hour, and unfortunately, it is not possible to view the Wishes Nighttime Spectacular from inside the restaurant. (You are correct - this is scheduled for 9.00 p.m. on 26th September.)
The only way around this would be to try and alter your reservation, which I think would possibly be a challenge, but it might be worth a try, and cancellations do occur. Please call (407) 939 3463, or check
online. Otherwise, perhaps you could visit the Magic Kingdom park on another day to view the fireworks? You can also view them from the beaches of Disney's Grand Floridian Resort & Spa, and Disney's Polynesian Resort.
If you have any other questions, please come back and ask me - I would be happy to help you plan your magical vacation!