I read that you have to use the older version of the raspberry pi image installer, not the latest as the new one breaks the WiFi config. Maybe that’s your problem.
So after I made the post yesterday, I set the node aside. I plugged it back in this morning and there was immediately a lot of disk activity for several minutes, the network connection came up, and I could get to the dashboard. It appears to be fine.
This was not my only try at this. I used two RPi3B+, two SDcards, and tried this multiple times with multiple images before the first post. I had also tried a power cycle on multiple images before THIS time it finally worked!
So I looked for a difference, found an older RPi 3B Rev 1.2 rather than the two RPi 3B+ Rev 1.4, and it came up perfectly the very first time. So something different between the RPi 3B and RPi 3B+?
There shouldn't be, but you may need to do an eeprom update of the v1.2 unit from an 32-bit OS first? That's just speculative though. I believe that you need certain firmware, that comes with the normal package stream, to do 64-bit on Pi 3s.