Assigned Role can not see navon

Hi all,
Our ‘Marketing’ (role) users started noticing that they can not see all the navons in all the folders. After checking the item properties for the ‘invisible’ navons, I (Admin) can see that only Admin is listed under Assignees(Type). That explains the invisibility for the ‘Marketing’ role.

What is strange is that the workflow has not been edited for a long time and all the states in the workflow still have both Admin and ‘Marketing’ as Assigned Roles (AdHoc Type disabled). Transitions only require one approval to move on to a different state (which is usually done by ‘Marketing’).

I should mentioned that we recently upgraded from 6.5.2 to 6.7.

Anyone aware of what could be causing this?

Thank you
Igor