Unfortunately, that won’t work. When you see “placeholder“ as the DTH, that means it is a cloud to cloud integration, not using the regular DTH construct that hub connected devices do. There’s not an individual DTH for the device, but rather a communication from that device’s controlling software ( which may be on the device itself or elsewhere) to the smartthings API.
If the device itself has an open API, you can write your own integration to substitute. But I don’t believe there is a separate one for the smartthings appliances. So you would still access it through the smartthings cloud, although of course you don’t need a SmartThings Hub.