Domain Mapping occurs very early in the email pipeline.
The mail logs do not show when a domain has been mapped to another domain.
I do see a couple of internal enhancement requests were filed to allow this, however never materialised due to lack of associated requests.
For emails passing through CES the mail_logs should be updated immediately, it would take a few minutes for message tracking to update on the SMA though. You may want to review the headers for the test email to confirm what appliance it passed through and ensure you are logged into the right ESA.
Regards,
Libin