Darrell, I'm not familiar with this John Nisewanger, though there is undoubtedly a connection to Jacob Niswanger.
Jacob Niswanger left Frederick Co., VA in the mid to late 1780's and settled in South Carolina......eventually Laurens Co., SC. He was md. to Susannah Wright, dau. of George Wright (no marriage record has ever been found) ca. 1786-88. He eventually moved to the Tipton Co., TN area and died there in the 1830's.
You might check Holtzclaw's "Ancestry & Descendants of the Nassau-Siegen ????" for any reference to the abovementioned John Nisewanger. It has quite a bit of information on the Niswanger family, but beware that some of the information has been proven to be erroneous.