You need to remove or disable in SS first, otherwise it will just re-include itself right after you exclude it, which is possibly what happened in your case.
Not sure it sometimes says unknown device, another bug in z-wave since they added LR support.
Best thing to do would be to run the exclusion and then reboot the hub, then check the z-wave details again. This will clear up any leftover LR nodes that get stuck in the list sometimes (cache maybe?).