Just wanted to add where I finally found the old forwarding option in GSuite.
- Admin Console.
- Click Main menu ( three lines ) in top left, hover over Apps, click GSuite.
- In the GSuite services list click Gmail.
- In the Gmail settings menu, scroll to the bottom and click Advanced settings.
- In the Advanced settings, General settings tab, scroll to bottom.
- There is a routing section with the 'Catch-all' 'Forward the email to' setting.