docs: External CRD fast follow (#21313)

* ESM

* TGW note

website/content/docs/k8s/connect/terminating-gateways.mdx

@@ -86,7 +86,7 @@ $ export CONSUL_HTTP_TOKEN=$(kubectl get secret consul-bootstrap-acl-token --tem
 
 <Note>
 
-Consul on Kubernetes now supports the `Registration` CRD to register services running on external nodes without a terminating gateway. We recommend registering services with this CRD instead of deploying a terminating gateway. For more information, refer to [Register services running on external nodes to Consul on Kubernetes](/consul/docs/k8s/deployment-configurations/external-service).
+Consul on Kubernetes now supports the `Registration` CRD to register services running on external nodes with a terminating gateway. We recommend registering services with this CRD. For more information, refer to [Register services running on external nodes to Consul on Kubernetes](/consul/docs/k8s/deployment-configurations/external-service).
 
 </Note>
 

website/content/docs/k8s/deployment-configurations/external-service.mdx

@@ -19,6 +19,7 @@ Previously, the only way to register an external service when running Consul on
 
 The process to register an external service in Consul on Kubernetes consists of the following steps:
 
+1. [Start Consul ESM](/consul/tutorials/connect-services/service-registration-external-services#monitor-the-external-service-with-consul-esm). You must use Consul ESM to run health checks on external services.
 1. Define the external service and its health checks in a [`Registration` CRD](/consul/docs/connect/config-entries/registration).
 1. Apply the CRD to your Kubernetes cluster. Internally, this action triggers an API call to Consul's [`/catalog/register` endpoint](/consul/api-docs/catalog#register-entity) to register the service.
 1. When using Consul's service mesh, define [service intentions](/consul/docs/connect/intentions) between the external service and services it communicates with.