Unfortunately the original topic was closed, but in case anybody searches for this info, here it is:
To enabled cache purging of partial content etc. the following worked for me:
wp --path=/path/to/wordpress option add rt_wp_nginx_helper_options --format=json '{"enable_purge":"1","cache_method":"enable_fastcgi","purge_method":"get_request","enable_map":null,"enable_log":null,"log_level":"INFO","log_filesize":"5","enable_stamp":null,"purge_homepage_on_edit":"1","purge_homepage_on_del":"1","purge_archive_on_edit":"1","purge_archive_on_del":"1","purge_archive_on_new_comment":null,"purge_archive_on_deleted_comment":null,"purge_page_on_mod":"1","purge_page_on_new_comment":"1","purge_page_on_deleted_comment":"1","redis_hostname":"127.0.0.1","redis_port":"6379","redis_prefix":"nginx-cache:","purge_url":"","redis_enabled_by_constant":0,"smart_http_expire_form_nonce":"19aab78f2b"}'
You can adapt any options to your needs.
To delete the option to add it with changes again run:
wp --path=/path/to/wordpress option delete rt_wp_nginx_helper_options
The original issue is this one: Updating 'rt_wp_nginx_helper_options' with WP-CLI