Worker Node group doesn't join the EKS cluster

1) I've set up the infrastructure using open5gs-infra.yaml
2) I've configured the bastion host and run step 5 properly (by providing the correct ARN value)
3) I've initialised the DocumentDB
4) I updated the CoreDNS configmap and restarted coredns pods
5) I then ran the cloudformation yaml file for the creation of the worker node group
6) However, the workernode group doesn't join the cluster. I've double-checked the parameters that I feed to the cloudformation template. I've even tried to edit the authConfig manually after the worker node group has been created so that the worker nodes can join the cluster. But that doesn't work.

Since there are no worker nodes, the pods can't be scheduled and the cluster is non-usable. What can I do so that the worker node group joins the cluster?