Looking for kube-controller-manager in rancher 2.5.15

I have a rancher v2.5.15 installed via docker images running a 9 nodes k8s v1.19.16. All my services are running well.
I’m trying to setup minio-operator and from what I understand from Deploy MinIO Operator on Kubernetes — MinIO Hybrid Cloud Documentation , I need to setup a custom certificate at kube-controller-manager but I don’t find it in kube-system namespace. My best guess is “calico-kube-controllers” but I don’t know how to adapt this setup.
Someone could suggest some hints?
Thank you by advance.