Indeed it works just fine now, powering from either USB or from my board assembly with the tuner connector, using the 5v "Vbus" pin to power it like I was doing before the malfunction. And now, with that TI codec chip removed, nothing is getting hot any more. I still don't have I2S any more and I have to fall back to analog, though. Which works, but I really miss the cleaner sound that the I2S connection gave me.

I wish I knew which component was the failed one and whether or not I caused it.

I have high hopes for that other breakout board. I ordered one too. Once I get that smaller breakout board, what's your recommendation for which pin to power it from?