You should be able use the same container with,
define( 'WP_CACHE_KEY_SALT', 'example.com:' );
or
define( 'WP_REDIS_PREFIX', 'my-site' );
Please see redis-cache/INSTALL.md at develop · rhubarbgroup/redis-cache
I have noticed one issue with this Plugin so far. It FLUSHALL all redis data...