If you try to deploy a secure checkout domain in 2020.2, the deployment will fail after a day or 2. The only 'workaround' from NS support is to first create it as a secure web store first. However, if you do that, it removes the primary domain from the set up website record, won't let you select any of the http domains that were in use before, won't let you edit or delete the deployment of the new web store domain, and changes the live site to shopping.netsuite.com.