Nest won't connect to wifi after power outage

[Beaverhollow6]

Hi! 

Trying to fix my dad's Nest connection. He moved recently and successfully connected the Nest to his new wifi network in the new house. Everything was fine until a power outage, after which the Nest will not connect to wifi. 

We've tried (multiple times): 

-Restarting the router 

-Factory resetting the Nest 

-Uninstalling and reinstalling the Home app

-trying to connect under both the new and old home locations listed in his Home app

I keep getting to the part in the Home app where I'm adding a new device (after factory resetting the Nest). His phone is too old to have QR code scanning built into the camera app, so I select "No QR code" and manually type in the code displayed on the Nest screen (I'm sure it is correct). I get a message "Home app wants to use a temporary wifi network to connect..." and the network name is NestHub7349.7349.ync, 

I select continue and am prompted to select a wifi network and enter the password (I'm sure it is correct). Both the phone and the Nest will then say "Connecting..." but it times out and the Nest goes back to it's "Can't connect to Wi-Fi" screen and the phone just displays an "Unable to connect, check your network name" error with an option to cancel or try again, which does the same thing. 

Thanks for any ideas! We're stumped as to why a power outage would cause this. 

[Beaverhollow6]

OK, I don't think this would matter, but it turns out that it wasn't a whole-house power outage. Just the circuit that the Nest was plugged into tripped and they don't know why. But the Nest was plugged into a surge protector. So the wifi in the house would have stayed on while power to the Nest was cut and restored. Still don't see how this would lead to a connectivity issue. 😕