Any way to salvage a fried Seed?

I just smoked my Seed by probing around mindlessly and connecting -12V from my Eurorack case to pin 28 (GPIO21/ADC6). Is there any sort of protection component on the MCU that I would’ve burnt that can be replaced, or is the unit just dead? I’m guessing not but figured I should ask. FWIW pin 28 is one of the GPIO pins that the datasheet says is merely 3.3V tolerant rather than 5V tolerant.