Not a doctor myself, so you shouldn't base your decisions on my comment
But from I understand, NAC protects you by blocking damaging components. I would say if you take paracetamol + NAC, one (the nac) will make the other(=paracetamol) useless. Can't have a cake, and eat it too lol
NAC does protect the liver, that a fact. It's also used to treat paracetamol overdose which otherwise, would kill the liver. I don't know how to interpret that sentence you cited
I have read twice to understand how humans are supposed to know alien species and why that's important