Need help generating an egress gateway (documented command not working)

Config
1

I raised an issue here https://github.com/istio/istio/issues/21379 because the supplied command doesn’t work. Any idea how to pass the customized egress to the manifest?

I am on istio 1.4.3 and was following the instructions here https://istio.io/docs/tasks/traffic-management/egress/wildcard-egress-hosts/#setup-egress-gateway-with-sni-proxy

$ cat <<EOF | istioctl manifest generate --set values.global.istioNamespace=istio-system -f - > ./istio-egressgateway-with-sni-proxy.yaml
> gateways:
>   enabled: true
>   istio-ingressgateway:
>     enabled: false
>   istio-egressgateway:
>     enabled: false
>   istio-egressgateway-with-sni-proxy:
>     enabled: true
>     labels:
>       app: istio-egressgateway-with-sni-proxy
>       istio: egressgateway-with-sni-proxy
>     replicaCount: 1
>     autoscaleMin: 1
>     autoscaleMax: 5
>     cpu:
>       targetAverageUtilization: 80
>     serviceAnnotations: {}
>     type: ClusterIP
>     ports:
>       - port: 443
>         name: https
>     secretVolumes:
>       - name: egressgateway-certs
>         secretName: istio-egressgateway-certs
>         mountPath: /etc/istio/egressgateway-certs
>       - name: egressgateway-ca-certs
>         secretName: istio-egressgateway-ca-certs
>         mountPath: /etc/istio/egressgateway-ca-certs
>     configVolumes:
>       - name: sni-proxy-config
>         configMapName: egress-sni-proxy-configmap
>     additionalContainers:
>     - name: sni-proxy
>       image: nginx
>       volumeMounts:
>       - name: sni-proxy-config
>         mountPath: /etc/nginx
>         readOnly: true
> EOF
could not read values from file -: open -: no such file or directory