Given the failure of the previous visit to the unit (during which the setup code was retrieved from the back of the Nest), I asked another person (not a technician, but someone comfortable with using the app, at least, with me on the phone remotely) to visit the unit and try to complete the setup using the Google Home app locally. Initially we were finally able to get through setup successfully and bring the Nest online, but because we had got the wiring information incorrect, the Nest only had the option to turn on the heat, not the A/C. We redid the setup with the correct wiring information, but when it got to the connectivity stage, the Home app couldn't connect to the Nest unit (even though it had successfully connected minutes earlier). An additional attempt at redoing setup ran into the same connectivity issue.
Finally the setup person had the idea to perform a reset on the Nest, and found the instructions on the Internet. That allowed the setup to pass the connectivity issue and complete, and the Nest was again fully functional and able to cool the unit to a more reasonable temperature.
Ultimately I found it disappointing that the Nest product would allow things to get to such a stage. Given the importance of being able to heat or cool one's property, there should be more support for putting the Nest in a basic mode where it can be controlled manually. It should offer the option to skip setup and operate in basic mode until setup is completed.
