Hello and blinky work. BT does not.

Ok, so the CPU and UART works :-)
And, the 32KHz clock domain works, hence the blinks.

Now, CPU can run from internal High Frequency RC or External crystal.
If your 32MHz crystal on the board has dry solder (or what ever has happened), then most probably internal RC remains to clock the SoC.
But 2.4GHz radio will not be 2.4GHz.

Zephyr v1.9 has Radio Direct Test Mode implementation, hci_uart sample can be used with DTM HCI commands to test the radio. The DTM HCI commands will fail to respond if the HF clock cannot source from a stable crystal.

And, yes nitrogen_beacon.hex from http://builds.96boards.org/releases/n
itrogen/zephyr-1.8/ flashed to the nano2 advertises. There's no console
output as I explained previously.

I'm now more convinced that the devices somehow got damaged in transit
from Seeed.

Very unlikely (and likely based on conditions), I use nRF51 dongles over 5 years now, carry it around in bare hands, worst I have done is to have my 32KHz crystal go out of its spec. but BLE operational using the 32KHz RC.

I'll report when I get the ones I ordered from Digikey. I expect them
to work just fine.

If you are curious about what happened to the radios, I'd be glad to
send you the 2 I got from Seeed.

I think Seeed need to contact our support (I am just a software guy).

The shipment didn't seem to have been opened. I'm pretty ESD conscious
at my end.

Steve