@sebum - The iOS wrapper library handles the redirect between the browser and native application. It cannot determine which third-party application is required to complete the authorization flow. It should be the responsibility of the third-party app to navigate back to the application that initiated it (if needed).
MFA using Okta Verify does work today - it just requires the user to bring the previous application back to the foreground. Once your application is back in the foreground, the browser view will still be visible - and the user will immediately be redirected back to your app.
Hope that clears a few things up!