Oops... Over Voltage

Managed to get a regulator put in incorrectly and hit my photon with 12v dc.
The led went on very briefly and then nothing.

Subsequently and unsurprisingly, USB doesn’t work or putting 5v in to the Vin pin. I did put 3.3 volts in to the 3.3v pin and it sort of works. It did connect to wifi and did send notifications, though the led brightness wasn’t as expected and I don’t think program flow was correct.

What did surprise me was what appears to be an inductor next to the USB connector got very hot.

Did I just blow the regulator on the board? Or is it likely that I managed to damage the processor or other hardware as well?

I’d prefer to resurrect the board, and to that end, any thoughts on what else to check on before I dig in to work on this thing?