2 Hubs, 2 Thermostats of the Same Model, One Hub Sees it as a Zigbee Thing - Help!

Two possibilities…

  1. The devices have different firmware, causing them to have different fingerprints and one of the fingerprints is not yet included in any of the edge drivers. It can happen.

  2. for whatever reason, the pairing for that specific device failed, leaving the manufacturer or model number either blank or all zeros. This also will cause the device not to match with any edge drivers. See the FAQ on that one:

FAQ: Manufacturer/Model Shows All Zeroes

Anyway, in either case, the first thing is to carefully check the fingerprint of the differing devices to see if they are the same or not. The information on how to do that is in the FAQ linked to above if you need it.