autoSSL issue with existing wildcard certificate

I have a domain running Wordpress multisite, which needs a wildcard *.mymultisite.com certificate, since my customers can create any subdomain they want. Later, the subdomain is mapped to the client's real domain name (e.g. myclientsite.com). I then attempt to enable autoSSL by creating an add-on domain. When autoSSL runs, the existing wildcard certificate gets installed because it matches the servername value. autoSSL won't issue an new certificate to cover the add-on domain because it won't uninstall/replace the valid, non-autoSSL wildcard certificate. So I end up with this: myclient.mymultisite.com: covered by existing wildcard cert, validated as secure. myclient.com: domain name does not match certificate, unsecure. www.myclient.com: domain name does not match certificate, unsecure. Is there a way to get around this and get autoSSL to handle the add-on domain names?