By default, we do not create a cluster-admin role and role binding when running an Existing Cluster installation with kots install (because we cannot presume cluster-wide permissions by default). Instead we just use a role and role binding for existing clusters. This is why the “Clusters” tab appears for an embedded install, but not for an existing install. That being said, if sufficient permissions are available, it is possible to get the cluster management tab to appear.
To switch that mode, it’s not documented, but it’s simple:
You’d have to just create the RBAC policy in that file ^^^ and then change 1 env var in the deployment: kURL/api.yaml at main · replicatedhq/kURL · GitHub