Does WP Rocket Support Memcached?

WP Rocket does not have an option for Memcached included, but you can set up and use Memcached along with WP Rocket with no issues, by using an additional plugin:
e.g.  https://wordpress.org/plugins/memcached-redux/

If you are a SiteGround customer, your hosting plan may include the ability to easily activate Memcached.