Here are some notes I have collected on Benjamin and Susan Davis. I really have not seen any definite documentation that his wife was a REWIS. Descendents of Benjamin Rewis have told me she was a REWIS. Benjamin Davis definitely lived near John and Mary Rewis and by the 1848 and 1849 Tattnall Co, GA Tax Digest, he certainly was closely connected to the family in some way. John and Mary Rewis did indeed have a daughter of Susan's age. You make the call. Do you have deed and probate documentation on Benjamin and Susan Davis. Sometimes things are mentioned in those documents that can give you a clue to this mystery.
1830: John Ruis (M60-70) appears in Tattnall Co, GA census, page 378. Also included are F40-50, M20-30, F20-30 (is this Susan?), M15-20, F15-20 (is this Maryann?), F5-10, M<5. Edward Conner (M30-40), enumerated with F20-30,M10-15,F5-10,2F<5, is a next door neighbor to John Ruis.
1840: Benjamin D. Davis appears as head of a family in GMD #351 in Tattnall Co, GA census, page 271. Enumerated are M40-50,F30-40,2M5-10,F5-10,F<5. Next door neighbor to John Ruis Sr.
1841: Benjamin D. Davis received a land grant of 565 acres in Emanuel Co, GA. Recorded in Georgia Land Grant Book U.5, page 301.
1848: Benjamin D. Davis, as agent for Mary Rewis, appears in Tattnall Co, GA tax digest in District 351, managing 1,139 acres.
1849: Benjamin Davis, as agent for Mary Ruis, appears in Tattnall Co, GA tax digest in District 351, managing 1,479 acres.
1850: Benjamin D. (M40) and Susan (F40) Davis appear as heads of a family in Tattnall Co, GA census, page 356. Enumerated as owning property worth $100. Mary Ruis appears on page 355B.
1860: B. D. (M50) and Susan (F50) Davis appear as heads of a family in GMD #58 in Emanuel Co, GA census, page 934. Enumerated as owning property worth $400.
1870: Ben D. (M60) and Susan (F60) Davis appear as heads of a family in GMD #45 in Bulloch Co, GA census, page 192B. Enumerated as owning real estate worth $500 and personal property worth $500.
1880: Benjamin Davis (M69) appears in the family of Wiley and Louisa Davis in GMD #47 in Bulloch Co, GA census, page xxx.