Is this the right set of records for Route53 domain to point to a mapped domain in a multisite?

My question is about whether I have the right record sets on Route53 for a mapped-domain. I have a domain at Route53 called domain.org. I have a multisite setup at mult.com. There is a subdomain sub.mult.com on that multisite. I have added a mapped domain, domain.org to be the fqdn for that sub domain. I have a letsencrypt wildcard on mult.com and it handles all the subdomains. But for each mapped domain I have to add in the SSL. When trying to do it for this Route53 domain it fails. On Route53 I have an A Name record pointing to my public ip for my ec2 on aws. I also have a CNAME record pointing to domain.org. Is that set of records on Route53 even correct to begin with? It seems there are a lot of ways to configure this setup and I cannot seem to find the right one. Any ideas greatly appreciated. I've read all the similar questions. I add that I am using the WP Ultimo plugin and it sets the alias to be the mapped domain.