I just fished one of these out of an e-waste bin and got it to work with my SmartThings v2 hub. The trick is to put your hub into General Device Exclusion mode and trigger the device to unpair itself (if it was previously paired with another hub which was the case with mine)
It’s a bit tricky to find that menu. You can find it in the SmartThings classic app under:
Hamburger Menu (bottom right on main screen)
Tap on "Hub is Online’
Scroll down and tap on Z-Wave Utilities
Tap on General Device Exclusion
Now follow the directions for the device’s manufacturer to exclude it from a hub. I just held the button down while I plugged it in, waited a few seconds, depressed the button, then pressed it again. At some point the app acknowledged that it saw a device exclude itself and I was then able to add it the usual way through the SmartThings “Add a Thing” menu.