I know the issue above as you mentioned since I build different certs all the coming the same error.
After fresh sleep and wake I have realised that some mistake with the certs. i have read my cert with
openssl x509 -subject -nameopt RFC2253 -noout -in /root/t/wazuh-certificates/soclab.bb.local.pem
This is not matching as you mentioned below your config, then graylog started and able to access GUI
I REALLY APRICATED YOUR HELP AND THANK YOU
I WAS BIG TIME USER OF SYSLOG PROJECTS (BEEN USING SYSLOG FOR MORE THAN 2 DECADES)