How to add allowed callaback URLs?

I’ve narrowed down the scope of what am attempting to do. Using the React Native Debugger, I have been able to ensure that I am correctly formatting the callback URLs.

Unfortunately, I am encountering the same white screen as described in Blank White Screen on redirect to Auth0 which appears to have never been resolved.

I see nothing in any logs the we are capturing to indicate what is wrong. Please advise.