There was a recent update/enhancement in Bulk Send so if you are creating a new process you need to follow the new guidelines. The enhancement now supports multiple recipients so each bulk recipient can have a different person as the second or subsequent signer. This means you can upload a list of employees and each employee can have a different manager defined as the approver in a workflow.
Read about (https://support.docusign.com/en/guides/ndse-user-guide-multiple-recipient-bulk-send) Bulk Send for Multiple Recipients .
The column headers in the CSV file must specify both the recipient role defined in the template and the Data Label of the field assigned to that recipient on the document. So if you have a template role called "Employee" and a Text field with the Data Label called "Pay" on the document you would need to provide 3 columns of data in the CSV for each employee with the respective labels Employee::Name, Employee::Email, Employee::Pay.
Regards,
Michael