I checked out this test site Online LDAP Test Server - Forum Systems
Apparently LDAPS (SSL/TLS) is not enabled there so that is no help to debug.
queries like these work for me but neither does that help your issue.
ldapsearch -W -h ldap.forumsys.com -D 'uid=tesla,dc=example,dc=com' -b 'dc=example,dc=com'
I am not openssl savvy but this session may give you ideas Can't set up email in local environment