ExternalLayer.SetIsFrozen Help

Having some trouble with the ExternalLayer.SetIsFrozen node and wondering if others have experienced the same problem. The node works fine when I am freezing/thawing an layer that “lives” in the ExternalDWG that is opened. The issue I’m having today is trying to freeze a layer in the ExternalDWG that is from an overlaid xref. I am not able to get this layer to freeze/thaw. Is this something that is not doable with this node?