How do I know if my DKIM records are configured correctly?
Within Support, click the Admin icon () and go to Channels > Email, to confirm that the Custom domain for DKIM option is enabled. Enabling this option is required for it to be included in the headers of the email. Without the option being enabled, you may run into deliverability issues.
To validate the records, you will have to use a third party tool, as there is no integrated validator within the Zendesk product suite. Dmarcian is a common tool used in the industry for this purpose and can be found here.
The Selector would be zendesk1, zendesk2 in separate lookups:
For information on setting up DKIM records for your external address, see the following article, Digitally signing your email with DKIM or DMARC.