Have you looked at the Kumostat wireless tag sensors? The 13 bit ones have higher accuracy than most home automation devices.
They can connect with smartthings one of two ways, either through IFTTT or with a cloud to cloud integration created by a community member.
You do you need to buy their bridge as well. But they’re definitely worth looking at. Quite a few community members have been using them for use cases where the distance is longer than zigbee or Z wave will reach. You can ask if they are using the environmental features.