Absence Approval based on Worker's Assignment Details

Hi,

I have a requirement where based on Employee's Employmee category absence approval should take different flows. Challenge is i can only see available attribute GetRequestorInformationByUserNameResponse.result.employeeCategory which picks the Employee Category of the requested, let's say if Line Manager is submitting absence on behalf of Employee, it picks Line Manager's Employee Category and not Employee. How can we get Employee's assignment details in Absence Approvals, Please suggest.