You are likely out of App Engine quota. The quota has very little to do with the data storage, but rather datastore reads. More at https://docs.opendatakit.org/aggregate-deployment-planning/#minimizing-app-engine-fees. Either wait 24 hours for the quota to reset or add a credit card and enable billing.
As to the CSV, try downloading the data using ODK Briefcase (Docs at https://docs.opendatakit.org/briefcase-intro and latest release at https://github.com/opendatakit/briefcase/releases). Once you have that CSV, it will have all the data (including the media files) you'd like to work.
Finally, when you get a chance, please introduce yourself here. It helps build community!