Welcome, unfortnately I cannot clarify the information about the Bough Brothers only to say that It is believed that they came in from Dublin, Ireland. but hopefully you will glean some information.
I can share with you the following.
In my research the earliest Bough that I found is a George Bough. He is listed as 25 years old in the 1832 fcensus, free colored His race is listed as a mustee (the offspring of a White and Mulatto) George Bough mother is Sarah Beaudhuy a mulatto who was the property of Anthony Beaudhuy who was given her freedom as a little girl around 1779
The 1846 census, Free Colored lists George Bough with his wife a Susan Crow, and his mother Sarah Beaudhuy along with his three sons are listed as Edward born 1831, David born 1840, and Benjamin born 1842. I am the 3rd Great Grand daughter to George Bough. and am living on St. Croix.
The search is not over.lets make a joint effort.