While there are some workarounds...
* create a user on behalf of the recipient
* create a user that has the email address of an email distribution list
* create a forwarding rule in your email
...many of our users would like to schedule some dashboards to be sent via email with support for a pdf attachment to people who are not and will never be Sisense users in their system. Our application (we're OEM) supports this for reports in the application, and there's an expectation that dashboard emailing would exhibit the same support.
As it is clients have to create an application user per external recipient, log in as the user and SSO to Sisense to the recipient available as a dashboard subscriber. In some cases, work can be reduced with an application user that represents an email distribution group instead of an account per user, but even that requires a lot of maintenance from dashboard to dashboard as their recipient lists vary so much. The best work around is using forwarding rules in users' email clients so that when they receive the dashboard subscription, it's automatically forwarded to those external recipients. However, the forwarding process is then tied to a specific user's email account which introduces risk should change need making when they're not available, or the organization.
If the variability of filters and data security is the concern, then perhaps sending in the context of the owner copy is a step toward an answer without meeting the more robust needs of defining different data security for different non-user recipients of the same dashboard.
