If you cannot access Team Cloud with your iCloud account, you probably did not allow app to Look up your email. Change this in https://www.icloud.com/settings/ , Manage Apps That Can Look You Up. You need to do this on non mobile device.
You probably have original video stored on your iCloud and not in device. Please go to photo gallery and tap on edit for download or get latest Binary version from App Store > 5.7 and download via app.