Has anyone tried onboarding Power BI to IdentityNow? I was looking through their API Documentation and it looks like there is no API for User Management but they do have Get Group Users API call.
I have not onboarded Power BI, but I have worked with the Microsoft Graph API. It might be the case that the Graph API for users is what you will use to get a list of users who have the PowerBI license. You can read up on how to query users by license type:
I think this API is what you will need to query the list of licenses in your org to find the SKU ID.