You asked for an interview "of any" protesters. I provide at least a few datapoints. The organizer of the rally took pains to call it a "pro-white" rally rather than "white supremacist". Some may consider them similar. 

The police estimated participation by these groups--
• 150+ Alt Knights
• 250-500 Klu Klux Klan
• 500 "3% Risen"
• 200-300 Militia 

The driver of the car was with Vanguard America, holding their "shield":
https://www.splcenter.org/sites/default/files/fields-vanguardamerica.png

This was a small rally, so these numbers are not just rare outliers.