Apple app review rejecting submission due to apple signup/in process. (linkidentity)

[Ruud14]

Apple keeps rejecting my submission because of the sign up/in process.
In my app users are anonymous at first, and during signup they are converted to authenticated users by means of the linkIdentity function which works great.

There are three ways to implement "Sign in with Apple"

1. Using an external browser.
2. Using a Safari View Controller.
3. Using native authentication.

Initially I went for option 1, as I do with all other third party auth providers. However, after a couple of times, my submission got rejected because Apple considers using an external browser a "Poor user experience" and they suggested using either Safari view controller or native authentication.

Hence I went for option 2, (using authScreenLaunchMode: LaunchMode.inAppBrowserView). This almost works great except for the fact that the user is not automatically redirected back to the app afterwards. It seems like this view controller does not support routing back to the app using deep links. (Online I read something about a SFAuthenticationSession that is necessary in order to make this work). Instead the user now has to manually tap "done" in the top left of the browser.
Of course, apple app review also rejected this because it again results in a "Poor user experience".

I would love to go for option 3, but native auth is not yet supported in combination with linkIdentity (issue #1111)

This leaves me in a situation where I can no longer get my production app approved.

I am considering skipping the linkidentity completely for apple until support for option 3 is implemented, but I'd rather not leave the anonymous accounts as orphans.

Is there any way around this or is there any workaround to make option 2 work?
All suggestions are welcome!