Georgia AG loves to use that charge for lots of things. Essentially it’s RICO if you plan a crime with at least 1 other person then they any step towards that crime. Even if that step isn’t by itself illegal. They would need evidence (ideally) that any of the charged protestors had planned a crime and that being at the protest was a step towards it. The actual crimes needed to qualify for RICO at the federal level is pretty slim and serious. Unsure what Georgia considers it.