Adding remote sensors

I have a remote location that has sensors I want to read with the home assistant instance at my home. 

the remote location network consists solely of a raspberry pi hosting tailscale,  a 4G mobile broadband router, A Tuya mulyimode (zigbee/Bluetooth) hub and sensors connected to that hub. 

I can get to the remote network using tailscale. I can see the Tuya hub in my Tuya/smart life app along with the sensors connected to it, but I can't seem to get it integrated into home assistant at home. 

in home assistant under "zigbee home automation"  there doesn't seem to be a way to add a hub. it only gives me the option of adding a USB zigbee coordinator. (I have also read that it is not possible to have more than one coordinator on the network?)

if I go into the Tuya integration, I can add the hub there but no sensors appear under it. there is only a one entity present called "problem"