Hi Jennifer!
Thanks for visiting the Moms Panel with your great question!
I'm happy to assist you.
Diamond Horseshoe in Magic Kingdom is indeed only open as a counter service dining location during 'Peak Times.' Currently, it is closed and having spoken directly to a Cast Member on your behalf, I've found out that the next time it is scheduled to be open is for Thanksgiving at the end of November.
Unfortunately, it doesn't appear as though Diamond Horseshoe will be open during Halloween season.
There are some other great
Quick Service Dining Options in Magic Kingdom to consider though! Try popping over to Liberty Square and check out Sleepy Hollow. This location offers delectable sandwiches served on freshly made waffles! There are both savoury and sweet options folded inside - to suit all tastes. We tried it for the first time on our family's most recent trip in June and it was a unique and tasty treat! My kids loved the Nutella with fresh fruit option while my husband thoroughly enjoyed the Ham, Prosciutto and Swiss. I tried the Sweet and Spicy Chicken. These delicious sandwich creations are served from 11am-5pm daily.
I could talk about Disney Dining all day long! Please write me back if I can assist you further Jennifer!
Thanks for your kudos to the Panel and hope to hear from you again soon!
Wishing you a simply Magical time at Walt Disney World!
Kirsten