Restricting access to parent documents in manager to users and hiding others

Put simply there are multiple blog authors, they each have a login to access their blog categories and add, edit and delete their blog entries. I have setup up access to their "categories" in the document tree as such:

Index
-submenu
--blog main page
---blog category page 1
----blog posting
----blog posting
----blog posting
---blog category page 2
----blog posting
----blog posting
---blog category page 3
----blog posting

When the blog authors login I only want them to be able to edit/add/delete their "blog posting" and have no access to any of the parent documents in the tree.

I have succeeded in restricting access through Manger Roles and Permissions and have the option checked in the manager configuration to show protected pages, however the real problem is they are able to see the greyed out documents for the ENTIRE site which is very unwieldily and confusing.

The site is quite large and there are literally hundreds of pages with many different sublevels.

Am I able to show only the direct parents of the documents they are able to edit or am I stuck with either unchecking show protected pages and allowing access to the direct parents?

So I take it there is no way to do so directly, however I did come across this hack (https://forums.modx.com/index.php/topic,34677.msg210661.html) which mimics some of the functionality thats is missing from Evo. Too bad the hack no longer works, I guess in 4 years some changes in the code have rendered it useless or I'm thick as it just doesn't work for me.

User management for sites with a large amount of content is really convoluted, seems to be a take all or nothing proposition for displaying a flat or permission based tree in the admin for authorized users - at least in Evolution...