Network techs have been known to be wrong ... not intentionally ... so my advice is to test yourself using nmap.
nmap -P0 -p LDAPPORT IPADDRESSOFLDAPserver.
A real one:
nmap -P0 -p 389 172.25.84.30
would show:
389/tcp open ldap
Means moodle server can talk to ldap on port 389 ... open.
On a server using LDAP for students only I do have openldap.x86_64 and openldap-clients.x86_64 installed even though Moodle doesn't really need it. Comes into play testing however.
Are you using Moodle Networking? That's the mnet in your auth ... shows it's turned on ... if not using, turn it off.
Yep, that ldapsearch command is 'involved' and not really a user friendly tool ... unless you are into LDAP. Am not myself.
For 'easier' testing and admin of a server I usually install Webmin - open sourced cPanel. It has it's own perl based web service one runs on ports like 100000 and a web based LDAP search that allows one to view the tree/forest/OU's etc. but not edit them - which is all you need for Moodle.
https://doxfer.webmin.com/Webmin/LDAP_Client
You do have to set that up to talk to an LDAP server with a user that can query the tree/forest whatever.
Once you do that successfully - which would have same settings one would use in Moodle for the BIND user, one can drill down via it's LDAP Browser into LDAP to find the OU's that contain users ... internet Schema ... which is the stuff moodle uses.
Can't share a screen shot as that would disclose too much info.
'SoS', Ken