Google Group Access Restricted - no way to request access visible

[PaxVobiscuit]

When I visit https://groups.google.com/forum/#!forum/controlplane-support, I get the following message:

This group either doesn't exist, or you don't have permission to access it. If you're sure this group exists, contact the Owner of the group and ask them to give you access.

I see no mechanism to request access. This URL is what the app provides when you click ControlPlane Support in Status Bar Icon menu.