When Abel walked outside, he looks surprised at her discovery.

"Really? Are you sure? You haven't check inside of the door yet? Let me go back inside and ride it out again. You go inside and check what's beyond the door."

Abel walked back inside the ferris carriage, and the ferris wheel turned again. Once his carriage reached the top and stop for a few minutes, the trap door opens again for a few minutes.

If they need to contact each other while Anastasia is trapped inside, they do have their phones to communicate!