Older snippet code is built here if not in config: https://github.com/zendesk/magento_extension/blob/master/src/app/code/community/Zendesk/Zendesk/Model/Observer.php#L85 and is inserted into config using this upgrade script: https://github.com/zendesk/magento_extension/blob/master/src/app/code/community/Zendesk/Zendesk/data/zendesk_setup/data-upgrade-2.0.5-2.0.6.php