In Life and Character of the Chevalier John Paul Jones: A Captain in the Navy of the United States During Their Revolutionary War by John Henry Sherburne (City of Washington, 1825) there appears a document written by Robert Coram as part of official testimony concerning the engagement itself. This document refers to the incident of a French warship accidentally firing, not once but, twice, on the Bonhomme Richard instead of the HMS Serapis. After the first broadside, midshipman Coram was sent forward by Capt. John Paul Jones with a speaking trumpet to order the French ship, the Alliance, to cease firing and lay alongside the HMS Serapis in prepapartion for boarding her. He states that he thought that he heard a faint reply of affirmation when a few moments later to his horror, the Alliance unleashed her second broadside. The account begins thus: "I, late midshipman on board the American ship of war le Bonhomme Richard, commanded by the Honorable John Paul Jones, at present on board of the Serapis, prize of the above ship, do certify..." This statement clearly indicates the Robert Coram was a junior officer aboard the Bonhomme Richard when the engagement with the HMS Serapis took place. The account concludes with this statement: "In testimony whereof, I hereunto subscribe my name, on board of the Serapis, lying in the Texel, the 24th of October, 1779". The document is signed Robert Coram. An asterisk appears beside Coram' name with the addition of this brief statement: "A brave, steady officer, of South Carolina, whose conduct in the engagement did him honor."
(Note: The captain of the Alliance, Pierre Landais, is not recorded in a favourable light by more modern writers or by biographers of John Paul Jones. He is mentioned as being "arrogant" and in other places as being jealous and spiteful towards Jones. For his having fired upon the Bonhomme Richard twice during the engagement with the HMS Serapis, he was charged by supporters of Jones with cowardice and incompetence at best and treachery at worst. He was court-martialed and dismissed form the French Navy for his actions during the battle.)
So, Commodore Gillon had another combat-tested junior officer to assist him in conducting the South Carolina and her crew across the Atlantic. That Coram stayed with South Carolina at least until she moored in Philadelphia, is confirmed by him being listed as the 5th Lieutenant aboard the South Carolina by John Mayrant in his pension application. Ross's book, South Carolina Patriots, has a citation for Robert Coram, that reads"...an officer aboard the frigate South Carolina".