I have a similar issue with anything with charcoal in it - while I don't get pimples all over, I do get 3-4 pimples in the same locations every time and they don't go away until I stop using the charcoal product. My theory: these are "exit points" for the detox properties of the charcoal. I think this simply because they are in the same spot every time. Maybe you could chalk it up to coincidence, but the only time I get a pimple on my hip is when I'm using a charcoal product. It has never had a pimple at any other time. The only time I get a pimple on my neck... etc.
I also wonder if it could be a reaction to tea tree oil. I'm one who can't use tea tree anything because it makes acne worse for me.
I don't think it's the soap recipe itself - although the CO is "highish" for dry skin, I wouldn't think it would contribute that much to drying out your skin to the point of causing more acne, especially with a superfatted soap. I think argan oil has some unsaponifiables, but I'm not sure off the top of my head. I'm more inclined to use argan as a moisturizer than in soap. The charcoal could contribute to a drying factor though... so it's possible that the recipe with charcoal is contributing to drying.
Last thought I have is that you have no animal fats in the recipe, are you adverse to using them? If not, I would swap out the palm for tallow or lard. I can't use vegan soaps on my face without breaking out (the rest of my body seems to be indifferent). There's something about the animal fats that my skin likes.