I have repeatedly tried including and excluding this simple device (a plug-in GE lighting/appliance switch), and while it appears to add to the network, the SmartThings app can’t control it. Attempts to repair the Z-wave network report errors for this device (failed to update mesh info / route), though in the developer IDE, I DO see on and off events from manually pressing the button the device.
I don’t understand why even very, very simple tasks with supposedly supported devices don’t ever seem to work consistently with SmartThings.
FWIW, when I have a device that is not physically installed someplace (like your device), I pair it with the hub by plugging it in to the closest outlet possible. I then test its operation, and then move it to its intended location and repair the network once or twice.
I even have an AC pigtail for switches so I can do this with switches before they’re installed.
So far no problems.
I did have my water heater switch go AWOL once. That involved going down to the garage with hub, 30 ft extension cord, and ethernet cable in hand. Here’s hoping the v2 hub has battery AND WiFi.