The story of "Edward and Margaret" is a mystery not yet solved. Please note the following quote:
Edward and Margaret Griswold
Edward GRISWOLD - bap. Jul. 26, 1607, Wooten Wawen, Warwickshire, England; d. 1687-1691, Clinton, CT. Son of George GRISWOLD and Dousabel. Edward married second in 1672 the widow Sarah (JAMES) BEMIS. Married by 1629 at Kenilworth, Warwickshire.
Margaret - d. Aug. 23, 1670, CT. Traditionally she is named as Margaret DIAMOND, daughter of John DIAMOND. Genevieve Tylee Kiepura writes in "Griswold Ancestry in England" (The American Genealogist 39:176-180) that "Edward GRISWOLD m. Margaret BLENCOW of Marston St. Lawrence, co. Northampton, dau of John BLENCOW and his wife Mary WALLISON." However, in "Note on the Ancestry of the Griswolds of Connecticut" (The American Genealogist 40:43-44), John G. Hunt conclusively shows that the Edward GRISWOLD who married Margaret BLENCOW is not the immigrant to CT, and Genevieve Tylee Kiepura concurs."
I have several other bits of correspondence but my (present)conclusion is:
The "Hicks" family say she wasn't a "Hicks" and the pedigree floating around for "Margaret Hicks" is untrue.
Blencow is positively out because of the above studies by the Griswold Family.
"Diamond/Dimond" is not accepted anymore although one correspondent claims she is Edward's second wife (?).
I go along with the Griswold Family and leave her last name blank. It's hard to do with so many candidates floating around, but that is what I'm doing.