Collect Kubernetes audit logs from local files only if node label exists via fleet

While trying to set up the "Collect Kubernetes audit logs from local files" with the Kubernetes integration in fleet, I was trying to add a condition to only collect logs if the node label kubernetes.labels.node-role_kubernetes_io_control-plane existed on the node. is this possible?
if not this is there a way to add a condition that checks for if a directory exists before attempting to read (condition not processor basically)
Tried ${ne(kubernetes.labels.node-role_kubernetes_io_control-plane, null)} and many other iterations without luck and the conditions linked at Variables and conditions in input configurations | Elastic Docs don't really apply.