Dynamic RLS with Dynamic Organization structure

[DirkVr]

I am trying to setup RLS using Hierarchical Organization structure. Users are not stored in Active Directory.

The following business rules apply

• A organization unit can have one or more sub-organizationunits
• The hierarchy is ragged, meaning the number of sub-organizationunits can vary in the tree (let's say up to max 5 levels)
• A user can have access to multiple organization unit. For instance we have on the highest level 3 regions (region1, region2 and region3). Person X can have to Region1 and Region3. 
• A organization unit can have multiple users.

On data level this corresponds to the following tables :

• A fact table where each record contains a Foreign Key (OrganizationUnitId) towards the OrganizationUnit table
• Dim_organization_unit which contains for each OU a record. IN this record we calculate the OUPath (using PATH function) and calculate up to 5 level-columns.
• A user table containing all users know in the system
• A link table (named "UserOrganizationUnit") which links a user to one or more Organization Units and vice versa.

I want to come to a RLS security, where the logged in userid is sent via CustomData to Power BI. Using the userid, I want to filter out all facts which belongs to the OrganizationUnit where the user belongs too PLUS all his sublevels.

Any tips how I should do this?

Below my datastructure