I live in Rock Hill and have a personal friend in the York County Sheriffs Department (he's a Constable). The Sheriff is very much aware of the Muslim enclave in York County. It is attended by the local SC Muslims, i.e. all black folks. There ain't no Jihadist/Middle East Muslims in the bunch.
Basically, its their substitute for Mecca. Its their religious retreat area, dare I say it, like a Christian Retreat Camp...
My friend has personally seen the facility (while on duty). There ain't nothing to worry about here. Besides, if there was, we know exactly where they are if we need to find them!!