Yes I was able to add the Thermostat to another 'Home'. My preference is
to have both Thermostats under the same Home. Appreciate if this can be
resolved.
I as well have the same issue in being unable to add second Nest
Thermostat to my Nest iPhone App. To note this 2nd Nest thermostat does
function and is on the same home network, just can not add it to 'add
this product' to my Home account.