Currently you can pass a 'Role' into Tableau Desktop when you connect to Snowflake to build a report:
However, when you try to connect from to Snowflake from Tableau Server after publishing a report there is no option to override the Role:
This makes it so users trying to access the published dashboard have that role enforced and that causes issues:
1. If the user is not part of that role in Snowflake, it errors and denies them access to the datasource.
2. If row level security is set up by role in Snowflake, it makes it so only users of the same role can access the dashboard, so there would need to be a different dashboard for each role for the same report.
However, if there was an option for 'Role' like their is on the Desktop version, this would allow the role to override the publisher's role, and allow any user with different roles to access the dashboard appropriately.