With respect to the Elastic Agent issue with the Suricata integration, I recommend to verify that the log path is configured correctly. Then check the logs from the Agent (see View Elastic Agent logs in Fleet | Fleet and Elastic Agent Guide [7.16] | Elastic) to see if there are any issues. You can share them here if you like.
Also to better help, please share the policy applied to Agent so we can see exactly how it's configured. See Elastic Agent policies | Fleet and Elastic Agent Guide [7.16] | Elastic.