The attack took place in the late night hours on Sunday after a puncture forced Mbisi and his driver to stop on a road close to Kruger-Mpumalanga International Airport in northeast South Africa.
While waiting for assistance, their car was approached by five heavily armed men in balaclavas who emerged from a black BMW that stopped nearby.
Mbisi received several shots, which turned out to be fatal. The driver was shot in the leg and is currently receiving medical treatment.
The attackers were reported to have fled the scene.
In September 2018, Mbisi was among six people who were arrested for allegedly forming a rhino horn trafficking syndicate responsible for a substantial proportion of rhino killings in Kruger National Park, one of the main rhino conservation sites in South Africa.
The syndicate included four former or current policemen and notorious local gangster Petrus Mabuza Mshengu known as “Mr Big”.
They were charged with theft, conspiracy to commit a crime, illegal buying and selling of rhino horns, corruption and money laundering but were later released on bail.
While Mr Big was assassinated in June 2021, things continued looking good for Mbisi for some time to come.
In October last year, he was, despite still facing the charges and attending court hearings, even inaugurated as the traditional leader of his clan.
The police said it opened an investigation into the killing.
South Africa is home to the estimated 80% of the world’s rhino population, which has been subject to intense poaching pressure since 2007 due to the booming demand for rhino horn in East Asia.