Thanks for getting back to me, Annatjie.As far as I can make out, the first John Benn in Knysna (1812-1877), the one who built the Annie Benn, had a brother William Benn, who was born in 1815.So, William's son, who perhaps was also called William (?), would then have been cousin to the second John Benn (1846-1934).
John Benn 1st left Mossel Bay for Knysna in 1855, in order to repair the shipwrecked schooner, Musquash.At some time between 1855 and 1868, he also ran a small hostelry "with tap."
Does this information fit with anything you've got?
What I would really like to find out is the Benn history before John Benn 1st camt to SOuth Africa.I tried contacting the historian Erna Katz at the Dias Museum in Mossel Bay, but my email was returned.Maybe I can try phoning. I live in the US, so the time difference makes it difficult to call.