Long shot, but… I have a HomeSeer ZIR000, a very early Z-Wave sensor that reported motion, light level and temperature. I can’t get it to pair. In fairness, this is V1.1 and is probably a bit over a decade old, but still, I have hopes…
You’ll need to do a general exclusion on it first, which is a little more complicated with that device, and after that you have to make sure that it’s awake long enough to do the pairing, which requires a separate step.
The Homeseer instructions are pretty good, but all the stuff in step one is about general exclusion so don’t get confused by that. You need to take the cover off the sensor, make sure the batteries are good, and then do the general exclusion.
https://support.smartthings.com/hc/en-us/articles/200878314-How-to-exclude-Z-Wave-devices
You don’t need to do step four, SmartThings automatically adds itself to the association group.
No telling if the device itself is still good, but if it is, that procedure should work for you. It’s just tricky because there’s a lot of timing stuff involved in making sure it’s awake at the right time. 
Thank you. It’s now seen just as a Door/Window sensor, no other data. Is that your experience?