Welcome to the Forum @Dustin_Monk and apologies for the inconvenience here.
Unfortunately, some of the emails sent from Asana can land in the spam folder. Can you please confirm you haven’t received this email as spam?
Another possibility could be the amount of tasks nested in the Project. That could take bit longer to generate the email. Have you attempted to export it again?
If this doesn’t resolve your issue, I would recommend you to contact to our Support Team providing the URL of the Project you are trying to export so they can take a closer look into this and assist you further. You can contact them following these steps: https://forum.asana.com/t/how-do-i-contact-support/19057/7?u=natalia
Looking forward to your reply!