There is no indication of communication errors in the vmware_vrlcm.log.
Aria Operations Manager 8.18.x
Aria Operations for Logs 8.18.x
Aria Lifecycle Manager 8.18.x
The integration is not yet configured.
Refer the documentation: Configure product details, on how to configure the integrations to work together for displaying health status.
Checking Interoperability, indicates that 8.12.2 should work with 8.18.0 or 8.18.1 of Aria Operations.
https://sim.esp.spespg1.vmw.saas.broadcom.com/Interoperability?col=1425,18335,10107&row=116
The download for 8.12.2 is available here: https://marketplace.cloud.vmware.com/services/details/vmware-aria-operations-management-pack-for-sddc-health-monitoring-8-12-2-2?slug=true