What you learn as part of your CNA training depends on what state you are in. What really matters is weather your future employer wants you to be CPR certified or not. I got mine because one of the places I wanted to apply at required it.
Don't appeal or contest the results. Yes it's possible that somehow they screwed up but it's far more likely you got the pulse wrong. Suck it up and try again. Immediately trying to blame others for what is probably your failure is not a good characteristic to have, so I suggest you work on that.