Anyone ever heard of this?

[JaxDually]

I have heard about bad alternators on newer cars shutting the vehicle down, no restart and causing low voltage fault codes on computer modules. From what I'm told if the alternator isn't putting out a certain voltage, the PCM will shut the vehicle down to protect the computer modules. The dealer is telling me that all at once the FICM and GPCM show low voltage codes and the IPR and HPOP are also showing trouble codes and that all 4 need to be replaced. When my '05 6.0 died it was showing no signs of trouble. I found out that one battery had a bad cell and the other only had 160 cranking amps shortly after it died. Could a bad alternator be my problem and could it explain why all 4 vital components appear to have failed simultaeously?