Judge Patricia Goliath accepted crucial CCTV footage which captured the kicking and beating of Kumalo in the early hours of April 14 in Ravenscraig Road, Woodstock.
Describing it as a "silent witness", she said CCTV footage had become crucial in the collection of evidence and the finding of truth in criminal cases.
She said the case had been based largely on circumstantial evidence that she had weighed up "holistically". Goliath found that the kicker and the driver of the Porsche 911 Carerra vehicle were indeed the same person.
Tracker evidence found that the Porsche, belonging to Mthethwa, was parked in Ravenscraig Road during the six-minute attack. Goliath said the defence's attack on the authenticity of the footage could not be accepted.