Removing Rancher from a cluster: cattle-system stuck Terminating, clusters that will not delete, the webhook that blocks everything, and getting the admin back
To wipe everything: the rancher-cleanup job and its verify job. For surgery: remove metadata finalizers (patch) and do not force the namespace spec.finalizers without first checking what resources remain; patch finalizers on clusters.provisioning and clusters.management; export and delete the rancher.cattle.io webhooks until the pod is back; reset-password inside the Rancher pod.