The Saunders couple - who had dual citizenship for South Africa and the United Kingdom - lived in Cape Town and were killed during a work trip to KwaZulu-Natal on 10 February 2018.
A trolley porter at Waterloo Spar in Verulam, who often helped Sayfudeen Aslam Del Vecchio when he shopped at the supermarket, was the main witness in the Durban high court on Monday.
Commemorated botanists murder: Accused claims witness utilizing him as scapegoat graziadaily.co.za - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from graziadaily.co.za Daily Mail and Mail on Sunday newspapers.
One of the accused in a case probing the murder of celebrated botanists Rodney Saunders, 73, and his wife, Rachel, 63, has claimed a witness is using him "as a scapegoat" for the crime.