OK,
As Mary told me on the side, only Martin D should play with permissions.

One moral learned. If you say for example, set the default site role for all users to Authenticated User, and change permissions for the AU, then you could have some issues. It will impact even the super admin.

For example, I lost notifications on my site administration menu. Called the super admin, same thing. I could not get to userpolicies to to change the default user to something else. I was able to get to the permission screens and change the permsiions for AU, then notification came back and I changed user policies default to student.

Now I am back to the enrollment key issue. I think it is a permission issue because I really got it to work, so I saw the "enter the key given to you" field but could not get in. Flipped permissions to inherit and I am back to where we were. I will see if key works on demo.moodle.net and take my clues from permissions there.

Chris