K8S - Switching Pod Definition from Jenkins GUI to yaml file leads to error with custom jnlp Container

I am currently struggling setting up a proper yaml configuration for the K8s Cluster our Jenkins Pipeline is running in (see below) .

Until now the whole configuration was set in the Jenkins UI, defining the cloud, the basic pod template and the different working pods. All of the working pods rely on a docker image, which were already custom made before I started working on the project. There is also an image for a custom JNLP container, which I need to use.

My approach was to use the use the output pod.yaml from the Jenkins Pipeline log (based on the GUI configuration) as a basic template for creating my own yaml. So all necessary parameters should be set correctly. I'm just wondering if the jnlp container is missing some credentials...Idk, I'm a bit lost as I'm just getting started with the relevant technologies and would very much appreciate your help, indeed. Thanks :)

The Error message I get is the following:

Dec 08, 2021 3:23:39 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Protocol JNLP4-connect encountered an unexpected exception
java.util.concurrent.ExecutionException: org.jenkinsci.remoting.protocol.impl.ConnectionRefusalException: Unknown client name: \cloud-work-z8vpq-snct7

View my code here:

Snippet from my Jenkinsfile:

stage ('PC Linux x64') {
  agent {
    kubernetes {
      cloud 'our-cloud'
      label 'cloud_work'
      idleMinutes 5
      defaultContainer 'work-docker-dml'
      yamlFile 'pod.yaml'
    }
}

YAML Configuration I created ("pod.yaml"):

apiVersion: "v1"
kind: "Pod"
metadata:
  labels:
    jenkins-work: "k8s-jnlp-agents"
    jenkins/label: "cloud_work"
  name: "cloud-work"
spec:
  containers:
  - command:
    - "/bin/bash"
    - "-ex"
    image: "artifactory.company.local:6013/work:ubnt20.04_dml_v2"
    imagePullPolicy: "Always"
    name: "work-docker-dml"
    securityContext:
      privileged: false
      runAsGroup: 1000
      runAsUser: 1000
    tty: true
    volumeMounts:
    - mountPath: "/net/example/examplemount"
      name: "volume-3"
      readOnly: false
    workingDir: "/home/jenkins/agent"
  - command:
    - "jenkins-agent"
    image: "artifactory7.company.local/company-docker/company-focal-jnlp"
    imagePullPolicy: "Always"
    name: "jnlp"
    securityContext:
      privileged: false
      runAsGroup: 1000
      runAsUser: 1000
    tty: true
    volumeMounts:
    - mountPath: "/net/example/examplemount"
      name: "volume-3"
      readOnly: false
    workingDir: "/home/jenkins/agent"
  hostNetwork: false
  imagePullSecrets:
  - name: "secret 1"
  - name: "secret 2"
  nodeSelector:
    kubernetes.io/os: "linux"
  restartPolicy: "Never"
  volumes:
  - emptyDir:
      medium: ""
    name: "workspace-volume"
  - name: "volume-3"
    persistentVolumeClaim:
      claimName: "example"
      readOnly: false