According to the Intuit docs
https://developer.intuit.com/docs/0025_quickbooksapi/0010_getting_started/0030_integrate_your_app/disconnecting_from_quickbooks/0020_disconn
After the customer clicks on the Disconnect link for your application in the Manage My Apps section of the App Center we redirect the browser to the URL entered in the Disconnect URL section for your application. It is important that you provide the correct URLs for both the development and production environment.
There is currently a bug in the development application environment where the redirect does not happen automatically. To simulate the proper flow you can simply paste the Disconnect URL into the browser after the App Center completes the disconnect process. We use this method to complete the testing during the technical review .