Back camera and back flash/LED not working (even after replacements)

I replaced the dock connector a few months ago and afterwards the back camera stopped working as did the flash/LED. The front camera is working fine as is the rest of the phone.

When I start the camera app the screen is black and the app crashes when trying to take a pic (other camera apps behave similarly). I can switch to the front facing camera in camera apps, but switching to the back camera again usually crashes the app. The backward facing flash/LED also is not working (e.g., when I turn on the flashlight app the button merely turns itself off again).

The back camera and LED didn't seem to be logically related hardware faults, but I did replace the flex cable (with the LED–no small feat!) and the back camera. Despite the fix, the faults with the back-facing camera and flash/LED persist (everything else is working fine.

Is this a problem with the board? I've tried hard restarts, but glad to try anything else that might come to mind :)