Hello!
There is a William Cameron who signed a petition to Sir John Johnson asking for the safe passage of his wife and three children from New York State to Cornwall (from the book "The Old Eastern District"). The United Empire Loyalist Heritage Centre in Adolphustown (uel.ca)has information on some of the Camerons that settled in Charlottenburgh, and possibly more resources to find William Cameron. They may be able to assist you in your search. You can send inquiries to research.uelc@gmail.com