Thanks @asmecher, and for clarifying about the user role.
I was able to find it after making the post.
Initially, I unchecked the box that says: Enable this journal to appear publicly on the site. When I did it, the journal was still showing up in web searches, even after some weeks. It appears that delete is the only way to remove a journal.
It is not clear why unchecking the enable box does not have impact. People can still access the journal.