SSL set-up is really separate from the theme. There is nothing in Avada which will stop you using SSL but the set-up process is completely separate. My suggestion would be to check Google for tutorials on SSL and WordPress. For example – http://www.wpbeginner.com/wp-tutorials/how-to-add-ssl-and-https-in-wordpress/
Note, the quote from the hosting company seems a little misleading to me and makes it seem like a bigger process than it really is.