I’d say ‘c’ is the closest to my position, though ‘misguided’ is your choice of words and not mine. I’m sure that some were there willingly while many were not. Some had a choice, but most probably did not. What is undeniable is that none served legally as combat soldiers until March of 1865.
We have crossed paths on this subject many times. I think it fair to say that you would feel that all CSA soldiers were "illegal" since the war itself, in the mind of many, was an act of treason.