I just used a time based trick when I needed to push through behavior that apple didn't like. 20 days after submitting the app one of the buttons changed it's behavior to allow a "File Open" dialog to go directly to the users root directory.
I set a timer for two weeks, after those the app started having its real behavior, with API calls and everything.
The whole Apple app review is a joke.
One could probably find a way of fingerprinting reviewer systems to directly hide the feature only for them.
We specifically allow-listed Apple's /8 range, but they don't always use the corporate VPN.