Redis Object Cache SSL Support?

Running a successful configuration of Redis Object Cache plugin with all underlying bits on a stand-alone Windows WordPress deployment. Redis is set to allow non-SSL and SSL connections. Non-SSL works fine. SSL does not work with the plugin, cannot understand why.

wp-config.php has the settings for the host and password and port and works fine to port 6379. What needs to be done to get it to make calls over TLS to port 6380?

tcpping, redis-cli, portqry all show 6380 as open.
But PHP log shows this:

"RedisException: read error on connection to ......server:6380 in D:\home\site\wwwroot\wp-content\object-cache.php:689
Stack trace:
#0 D:\home\site\wwwroot\wp-content\object-cache.php(689): Redis->auth()

Thanks.