Twenty-eight female guards were unfairly dismissed by a security company because the client‚ Metrora.
Trainer Nick Durandt said they postponed the fight after Schultz was diagnosed with bronchitis yesterday.
His doctor booked him off from training and fighting for four days.
"Make no mistake Mikey is as fit as a fiddle but I can't risk his health. He will be ready next week. We want to have a fair fight with both boxers in good health because we don't need excuses at the end," said Durandt, whose Boxing World will present the tournament jointly with Pat Molefe's Rainbow Promotions at Wembley Arena, south of Johannesburg.
The heavily tattooed and intimidating Schultz said: "This is my worst nightmare. I don't know if I got it from my wife or daughter because they both have flu.
"I'm grateful for the postponement, though. The doctor said I will be fine to begin training this week. I really can't wait to set the record straight with Maridzo."
Schultz's first-round stoppage by Maridzo was his first defeat against 15 wins (10 KOs) and two draws.
Their first fight took place at the same venue in November. It attracted about 3000 fans, who were mostly Schultz's followers.
They were vociferous until Maridzo landed a haymaker behind Schultz's ear. The South African hit the deck and a deafening silence followed.
One could have heard a pin drop. Schultz got up but did not have enough poise to continue and Durandt duly threw in the towel.
The tournament next week comprises five bouts. It will be bankrolled by Neo Africa. Durandt, a shrewd businessman, has included Jared "Hollywood" Silverman, another crowd puller, in one of the undercard fights. Silverman will fight Emmanuel Ndou, while Durandt's other fighters, Daniel Bruwer and Michael van Heerden, will fight Sean Santana and Michael Sangweni, respectively.
Welcome Ntshingila engages Pius Dipheko, while Ryno Liebenberg tackles Caster Ndou.
Tickets that were bought for this Thursday's match are still valid for next week. Tickets are still available at Durandt's gym in Norwood at R150 and R100.