According to the supersport.com website, Venter delighted the spectators at the venue near Kempton Park when he hammered Zack Mwekwassa to defeat.
But in the first semi-final bout of the series, Simba was again stopped in the first round, again highly disappointingly, by Thabiso Mchunu.
Referee Philip du Rand halted the bout 2 minutes and 46 seconds into the opening round when Simba failed to fight back, his right eye closing rapidly after a non-stop attack from Mchunu.
The rematch came after referee Tony Nyangiwe had stopped their first fight earlier this year in similar fashion, with Simba showing little enthusiasm for fighting.
Simba may well retire with a record of 12-4; 10 while Mchunu carries on from at 12-1; 10.
In the other semi-final, Venter stopped the powerful Zack Mwekassa after 2 minutes and 23 seconds of the fourth round, clinching his place in the final with a classic left hook out of a crouch.
The punch landed on Mwekassa’s jaw and dumped him on his back. He beat the count but was soon knocked down again. It took him a while to get back to his feet and to regain his senses.
Venter, whose record now stands at 14-5, with 10 knockouts, had also knocked Mwekassa down in the second round. His victim dropped to 13-3; 12.
Simba and Mwekassa are both from the Democratic Republic of Congo, but now based in South Africa.
Earlier, 31-year-old Sipho Taliwe beat Mzonke Fana on points to retain his WBC international junior lightweight title.
Taliwe won 117-110 on two cards and 115-112 on the third to take his record to 16-2; 10.
Fana, a former IBF junior lightweight champion who will be 39 years old in October, fought well and bravely, but may also contemplate retirement as his record fell to 31-5; 13.
The tournament was presented by Rodney Berman of Golden Gloves Promotions.
Results in the Last Man Standing boxing tournament at Emperors Palace, in Kempton Park, on Saturday night.
WBC junior lightweight international (12 rounds): Sipho Taliwe (holder) beat Mzonke Fana on points
Cruiserweight: Thabiso Mchunu beat Flo Simba, first round tko.
Cruiserweight: Danie Venter beat Zack Mwekassa, fourth round tko