Visibility to deconstruct a rig

I am deconstructing rigs to learn how they are built. While trying to deconstruct Arman Musovic’s free Hare Rig - geometry and controls are visible but the rig group is not. The rig groups visibility is locked in the (Attribute Editor - Display section) & is not visible in the channel box. When displayed in the channel box
via channel control it is still locked.
When I try to break connections in channel box stays locked.
I can’t find the connection that locks this in the node editor.

How do you trace the connections to find what is locking the visibility attribute?