This family may match the line I am researching. I have an Eliza Nideffer who married Thomas Campbell in 1874 in Carter County, TN.
Eliza was born abt. 1856. This may be your Elizabeth. Do you have a birth year on her?
Eliza had a sister named Mary born abt. 1860 who was living with Eliza and Thomas Campbell during the 1880 census in Carter County, TN. These two sisters may match up with this family. I'd be interested in learning more, especially since you have Mary listed also as marrying a Campbell.