User namespaces in the Developer Sandbox require a Network Policy to allow ingress traffic from other namespaces. Ingress traffic is required from both the openshift-virtualization-os-images and openshift-cnv namespaces in order for VMs to be provisioned successfully and to be able to SSH into the VMs.

It's preferable to have a unique label that does not need to change if the namespaces are renamed or other labels need to be changed. The request is to add a network.openshift.io/policy-group label to each namespace.