To view the Sent email status of an outgoing submittal, navigate to the Outgoing Submittals screen and scroll down to the Submittals Grid. Here you will see a "Log" icon - see red arrow in image below. Clicking on the Log icon will open the Email sending status log.
This image shows a Successful submittal.
When there is an error, an email will be sent to the sending user for them to review. Examples of error statuses are below.