Issue with Secured Custom Module Items Displaying

I have a custom module “Secured Docs”.
I have 3 secure zones - Brochures, Specs, Photos.

So, how do I filter the list display to show only the items that are in the secure zones that the user is subscribed to?

By default, if I have custom module items that are “Secured”, they shouldn’t show in the list display; but they do. Is this a bug or a coding error?

Secured items will still be listed (and their data can still be output via Liquid), it’s the URL endpoint (detail page) that is secured.

Unfortunately, there is currently no way to determine if an item is secured or not in order to filter them.
There is a backlog request for this here: Availability Of Secure Zone Status In Liquid

A possible workaround is to also tag the items with the names of the zones they belong to and filter by the tags according to what the user is subscribed to.