Original sentence: The effort was initially claimed to be successful, with the official in charge of the effort Lin Zexu, who wrote a "memorial" (摺奏) to the Queen of Great Britain in an unsuccessful attempt to stop the trade of the drug, as it had poisoned thousands of Chinese civilians (the memorial was given to Charles Elliott who refused to forward it to her majesty)
Edited sentence: The effort was initially claimed to be successful, with the official in charge of the effort Lin Zexu, who wrote a "memorial" (摺奏) to the Queen of Great Britain in an unsuccessful attempt to stop this illegal trade, which had poisoned thousands of Chinese civilians (the memorial was given to Charles Elliott who refused to forward it to her majesty)