Ok, I think I understand now... So you want anonymous users to be able to see when new pages are added, or existing pages have changed, BUT you don't want them to be able to see the actual pages themselves.
I know this type of thing can be done with search, so that you can return search results even for objects that a user group does not have permission for. However, I don't think there is any way to implement this type of thing for Tiki objects and "Recent Changes". Maybe you could use categories but I'm thinking that special page permissions would always override category permissions.
Perhaps somebody else has more knowledge or another idea of how you could do this.