The case was postponed to May 9 due to Krejcir's poor health, National Prosecuting Authority spokesperson Phindi Louw said.
Louw said one of Krejcir's co-accused, Bulgarian Lybohir Grigorov, who is a crucial State witness in the murder case, had still not finished giving his testimony.
The State withdrew its case against Grigorov in February after he presented new evidence.
Krejcir and his co-accused - Mfaniseni Memela, Nkanyiso Mafunda and Siboniso Miya - each face nine charges.
Grigorov had previously testified that he met Krejcir at the Harbour Restaurant in the Bedford Centre in Bedfordview, east of Johannesburg.
He said he had met Krejcir's friends at the restaurant, including Issa.
He added that Krejcir was involved in the exchange of gold and diamonds.
Grigorov said, when Krejcir was arrested for fraud by the organised crime unit, he moved his business to Money Point, a gold and diamond exchange shop in Bedfordview.
He met Krejcir's co-accused in the matter on their visits to Krejcir at Money Point.
Issa was gunned down in his car at an intersection outside the Bedford Centre mall around 06:00 on Saturday, October 12, 2013. Police found at least 30 spent cartridges on the scene.
Constant changes in legal representation and outstanding evidence documents have led to regular postponements in the matter since April 2016.
The State alleges that Issa was killed because he and Krejcir had argued over R500 000, which Issa had lent Krejcir for a bail application in another case.
Krejcir claimed his mother had sent him bail money and that it was Issa who owed him R500 000.