Hello:

I did find a company of Black Troops with the name "Hill City Guards," but they are from Lynchburg, VA. The date/era is about right for what you are interested in, also.

I think you will be able to access this page without a cookie, but I'm not sure. This clip is from "Record of the Times" (Wilkes-Barre, PA) 06 Jul 1880.

https://www.newspapers.com/clip/3566749/hill_city_guards/

I'll keep working on this.

Regards,
Hoyt