Can I change the CSR data when requesting the file from Zendesk Support?
The data from the Certificate Signing Request can't be modified to include, or exclude specific information.
Most of the Certificate Authorities provide a CSR generation tool that can be used to include the extra fields. You can also use an online CSR generation tool to issue the certificate request. A private key is also created when the certificate is requested with a Certificate Signing Request (CSR). Make sure to save the private key as this needs to be uploaded together with the SSL certificate issued by your CA.
For more details on uploading an SSL certificate, see Preparing a SSL certificate for upload to Zendesk.