For the tableau reports used in the dashboard we would need to sign in to Tableau again. If the user has already logged in to ADA (Okta for example) and accessing Gainsight and Tableau via it, the expectation is that the users shouldn't be asked to sign in again for the Tableau server based reports that are used in dashboards.
https://help.tableau.com/current/server/en-us/trusted_auth.htm