The issue is that, you cannot configure Directory Sync in AirWatch to VMware Identity Manager.
The image below shows the exact problem, where you cannot find the configure button in the Admin Console of AirWatch to configure the Directory Sync.
The reason why we do not see the configure button is because Directory Integration is not configured at the organization group.
Once you configure Directory Services at the Organization Group you should find the Enable button show up.
The image below shows the Enable Button highlighted.