while you may have a point that in the current state, companies won't willingly reduce their profits to do that, and maybe the only way to get them to make this change right now would be force them and create a massive bureaucracy to make it happen, this is not the only way this can be addressed.
for one, our governments could support african countries in charging more for the product. this could be done through trade agreements that are more supportive and less exploitative as they currently are.
say for example the price of raw cocoa may have to triple to ensure that the producers at the end get double of what they are getting now. (i think that was what was needed to bring the income to minimum living standards)
how much governance is needed to make that happen? once the trade agreements are fixed, it should mostly be spot checking the market prices to make sure the money ends up in the right places. that can't be that hard.