The alternator can still be "charging", i.e, putting out "over 12 volts", and it not be charging properly. The "cam sensor codes", specifically p0304, will come on when voltage drops to around 12.4 - 12.8 volts when the car is running. I've watched it happen when my alternator started "going". Normally the voltage will be around/over 14 volts for a properly charging system. It'll start dropping gradually and fluctuating, and eventually still be running in the 12-13 volt range.

You should be able to measure and monitor the voltage, not just at idle, but when running and driving it around, you'll see what I mean.
Or just change the alternator.

 

Oh wow, I completely forgot to update this! lol

I changed out the alternator and BOOM problem is gone.