Open Access dashboards do not show all the resources on a tile
Open Access dashboards may show less data than you see as an administrator. For example, a Status icon tile may list fewer resources, or a Performance line graph may show fewer lines than you see as an administrator.
This is because the Dashboard Server enterprise application may not have been given the same level of access that you as have.
In the Azure portal you can give the Dashboard Server enterprise application access to whole subscriptions, resource groups or just individual resources, see Enabling Open Access.