I'm scott, the developer that was rejected. The other app was 1000 ultimate experiences by lonely planet. After seeing it in the app store i can see how they might use the same gesture.

We asked the reviewer to clarify and they just replied with the same unclear language but specific to our app. They did specifically ask us to remove the "tap and pinch to expand gesture." When we replaced it with just the tap they let it through.

One thing I have to say is after trying the gesture on the device and not just the simulator it's was a little slow but still usable. We've since fixed it so we'll see if it gets through in the future.