The Trail of Blood is not accurate history at all, as baptists of today would consider the donatists and paulicians to be work salvationist heretics.
The fact is that the baptist churches are just not-historic at all, doesn't mean they arent right, but definitely nothing historic about em. No protestant denomination has any history behind it.
The catholic and orthodox do, but what kind of history? History of mixing in paganism to Christianity, history of infant baptism, veneration of saints and mary and other hocus pocus.
Whats my point? Who cares if there is a "direct line" of churches or something, lets just believe the Bible and stick with that