Family of ours in the Cape investigated the origins of our family tree and traced William Rosser to that region. They tried looking in all the settler records but could find no trace of William Rosser arriving on a passenger ship at the cape.
I have been handed down the family bible with the Rosser lineage written in the back of it, in that bible William talks about being born near the Forest of Dean in the UK.
I have been told that in later years he mentioned arriving in the country after a ship wreck in Cape Town but not much more was mentioned.
If you read the list of names on The Waterloo you will see that Rosser and Brookes were believed to have drowned in the wreck of the Waterloo that got into trouble along with the Abercrombie in 1842.
Rosser and Brookes got married to the Cordier mother and daughter in a church in Ladismith in the cape and our branch of the Rosser family originate from that area.
Cecil Rosser a relative of the family has done extensive research over many years and is probably the best person to talk to in this regard.