Vanity URLs cannot be made in Akamai if the vanity URL does not exist in AEM to begin with. Therefore, create them in AEM Dispatcher.
It is strongly discouraged to use a Vanity URL in an AEM page in Live Copy because the vanity URL overrides the default AEM page URL, which could negatively impact our internal and external linking and SEO strategies.
It is also strongly discouraged to create an AEM placeholder page in Live Copy to create a vanity URL. However, this sometimes needs to be done in the short term until the vanity URL can be published live on Prod. Follow these instructions to create the vanity URL. When the permanent, long-term vanity URL is published to Prod, unpublish and delete the AEM placeholder page to avoid conflicts in linking behavior.