I ran into an issue where a system dashboard created in Console and made available in Web Access was being treated as a personal dashboard in Web Access. According to my recollection, this may have been caused by my creation of the dashboard as a personal dashboard in Web Access and using the same name when creating the system dashboard in Console then overwriting the pre-existing dashboard in Web Access.
To resolve this...
I created a query in Web Access -- Module: User Interface; Object: Dashboard
There were two dashboards listed with the same name, one for Console, one for Web Access; the one for Web Access also had a user listed
I selected the Web Access dashboard, set the user to [Clear Selection], and saved it
Now everyone has access
Hopefully this will come in handy to someone if they run into the same problem, or someone can tell me if there is a better method to do the same.