I’ve found Mathesons Corner Road near Heriot in Otago (properly Matheson’s Corner Road, I’m sure). The article on Matheson place names in New Zealand has been updated. As well as Lake Matheson, Mathesons Bay and Mount Matheson, we know of 11 Matheson Roads, and one each of Matheson Bay Road, Matheson Bush Road, Matheson Way, Matheson Crescent, Matheson Street, Mathesons Corner Road and Mathesons Road in New Zealand.