“He performed an ovariotomy…”

“On Ovariotomy,” J. Marion Sims, The New York Medical Journal, Vol. 16, No. 6, December 1872, pp. 564-65.

“…he sent money to South Carolina.”

Sims’s biographer does not cite this, and does not indicate that Mittag made the request—though this seems highly likely, as Sims knew very few people in South Carolina at this time.

Harris, S. (1950). Woman's surgeon: The life story of J. Marion Sims. New York: Macmillan, p. 253.

“…a letter from Charles Bell Gibson…”

Gibson was named medical director of Virginia from the start of the war until his death. There is no proof that Sims either received or failed to receive Gibson’s letter, though the fact that it was preserved suggests that it did go through official channels. Sims does not remark on it; he died before completing his autobiography beyond the year 1861.

Letter from Charles Bell Gibson to J. Marion Sims, March 19, 1864, held at the Library of Congress.

“…he learned that Gibson had died…”

In Wilson, J. G., & In Fiske, J. (1891). Appleton's cyclopaedia of American biography. New York: D. Appleton, Vol. 2, p. 641.

“…now scrutinizing his procedures…”

See “…there were open challenges…,” above.

“…too bloody. too American…”

“Vaginismus: A Franco-American Story,” Peter Cryle, The Journal of the History of Medicine and Allied Sciences, Vol. 67, No. 1, January 2012, pp. 93, 81.

“…Sims put on another gathering for southerners…”

See “…a meeting place for southerners…,” above.

“…at last married Thomas Pratt.”

The Richmond Dispatch (Richmond, VA), May 24, 1864, p. 1; publication unknown; The Weekly Advertiser (Montgomery, AL), May 11, 1864, p. 2.

“…as though they somehow knew one another.”

See “…well enough to attend a ball…,” above.

I am imagining the encounter between Sims and the Maury cousins, but as noted above such a meeting was highly likely, and Anarcha would almost certainly have been a subject of conversation.