I have talked extensively with WP Rocket and it seems that they use CORS within their plugin. However, Cloudways also has CORS enabled within its CDN service. This causes conflict on most sites and if a conflict occurs when both services are enabled, CORS needs to be disabled on the Cloudways CDN to fix the conflict. I purpose that you include this information within your WP Rocket tutorial: https://support.cloudways.com/how-to-configure-wp-rocket-plugin-wordpress/?utm_source=Platformkb&utm_medium=kbsearch

Thanks