Aeotec Extender 7 - How does it work?

My Z-Wave network includes a Jasco in-wall switch (Rear Spotlights) that is mounted in an outside wall. That switch sometimes becomes unavailable or dead. So, I bought an Aeotec Extender 7 and plugged it into an interior socket close to the switch. I have just discovered that the switch is not connected to the extender, but rather the extender is attached to the switch, and nothing is attached to the extender (please see the attached map). This makes no sense to me as the Extender is closer to the controller than the switch. I have healed the network, but that makes no difference. Does the extender amplify without having devices attached? How does it work?