CDS View for Employee Manager

Hi SAP Folks,

I am trying to process PO workflow approval agent determination by getting the responsible person of the cost center and the person's manager.

Since I am only have the BP Number, I will have to get the Personnel Number to get the Supervisor for the succeeding steps.

So far, I have only found the following CDS views for this and both are Not released and cannot be used on Custom Logics. :

I_Employee

I_EmployeeLineManager

Is there any other way to get this information? I've only found FMs so far which is no longer applicable for ABAP for Key Users.