joining a worker node to a HA setup fails

Tried setting up a HA installation using curl -LO https://k8s.kurl.sh/bundle/f89c0f2.tar.gz

Master nodes installed fine (RHEL 8.6) but the join commands on the worker nodes fail with the following errors:

⚙  Join Kubernetes master node
+ kubeadm join --config /opt/replicated/kubeadm.conf --ignore-preflight-errors=all
W0627 12:58:21.669395    5789 common.go:84] your configuration file uses a deprecated API spec: "kubeadm.k8s.io/v1beta2". Please use 'kubeadm config migrate --old-config old.yaml --new-config new.yaml', which will write the new, similar spec using a newer API version.
[preflight] Running pre-flight checks
	[WARNING FileExisting-tc]: tc not found in system path
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
error execution phase preflight:
One or more conditions for hosting a new control plane instance is not satisfied.

[failure loading certificate for CA: couldn't load the certificate file /etc/kubernetes/pki/ca.crt: open /etc/kubernetes/pki/ca.crt: no such file or directory, failure loading key for service account: couldn't load the private key file /etc/kubernetes/pki/sa.key: open /etc/kubernetes/pki/sa.key: no such file or directory, failure loading certificate for front-proxy CA: couldn't load the certificate file /etc/kubernetes/pki/front-proxy-ca.crt: open /etc/kubernetes/pki/front-proxy-ca.crt: no such file or directory, failure loading certificate for etcd CA: couldn't load the certificate file /etc/kubernetes/pki/etcd/ca.crt: open /etc/kubernetes/pki/etcd/ca.crt: no such file or directory]

Please ensure that:
* The cluster has a stable controlPlaneEndpoint address.
* The certificates that must be shared among control plane instances are provided.


To see the stack trace of this error execute with --v=5 or higher
Failed to join the kubernetes cluster.

so apparently some certificates are not being generated?
Do I need to copy them manually from the master node(s)?

What also made me scratch my head was the kubernetes-master-address parameter in the generated join command for the worker nodes; it's localhost:6444 which seems wrong to me when running this script on the worker nodes?

Start by reproducing the worker-node join using the generated command and inspect /opt/replicated/kubeadm.conf alongside the missing certificate paths under /etc/kubernetes/pki. Compare the worker join flow with the master-node setup and verify the control-plane endpoint; done means a worker joins the HA cluster without certificate or endpoint errors.