Patrik Jordan Mathews came over from Canada in late August. Law enforcement circles have been following it since then because he is a known neo-Nazi and an all-around bad guy. These are plenty of news articles about it, you just have to look for them since they come from smaller sources.
So this really has nothing to do with the rally other than a couple of shitheads may have thought about going.
If this is the type of “intel” Coonman is using to clamp down on the rally, it doesn’t seem justified to me.