I think I asked a bad and unclear question. From the documentation you pointed me to, which I read BEFORE posting the above question:
Unknown Devices
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In either case, the database must be updated and you should raise an issue to get this addressed.
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Thus, my question is not how to add a ZWave device thing to my particular installation, but rather, in the case of an unknown device, how do I add it to the Things Supported by the Z-Wave Binding list at
https://www.openhab.org/addons/bindings/zwave/doc/things.htmlTEXTNOTLINK
or raise an issue? One thread, ZWave Device Add request: FF-ZWAVE5-ECO Firefighter audio detector, had a link to https://www.cd-jackson.com/index.php/zwave/zwave-device-database/zwave-device-database-guide which comes back as file not found.