In order to connect with https, even to redirect or process your “alias,” you have to have a valid SSL certificate for whatever domain the client sends.
The SSL handshake takes place before anything in the Apache server is processed. In other words, if you are not using a wildcard SSL certificate, the SSL handshake will fail for https://anything.example.combefore the Apache configuration file ever has a chance to process the alias.
Whatever else may be an issue, this must be corrected before any further diagnosis, if required, can be had. For example, if the desired behavior is that the https://anything.example.com be “redirected” to http://example.com you will probably have to use a mod_rewrite condition match as the RedirectMatch directive is only matched against the URL-path, and the use of ServerAlias will create the necessary match for handling the initial query, but will not attempt to “rewrite” or “redirect” the query to another desired URL.