Assign Customer ID parameter based on workspace for paginated report

For context...We are migrating from an old SharePoint implentation to a Power Bi premium capacity for our external reporting tool.  Each of our external customers is assigned a unique site collection for accessing there reports.  All of the existing reports that will be migrated are paginated reports.  These reports rely on a user id assigned to that SharePoint site collection.  That is important because our very first parameter stored procedure in each report is looking for that user id to determine what data the customer using that SharePoint site collection can access.

Is there a way to assign a user id to a Power Bi workspace that can be used as a parameter when rendering paginated reports?