This error is present in the Kibana logs you provided:
FATAL Error: [config validation of [elasticsearch].password]: expected value of type [string] but got [null]
That's due to a misconfiguration of the file /etc/kibana/kibana.yml, precisely the field elasticsearch.password. It should have the same password you entered when changing it with wazuh-passwords-tool.sh. Please change that and restart Kibana with:
systemctl restart kibana
Then try to access Kibana again.
Hope this helped,