The case evidence links to the controversial Czech fugitive from justice, Radovan Krejcir.
Speaking to the Mail & Guardian from Germany in the wake of the third anniversary of her husband's death last week, Christiane Gemballa said that although she was trying to move on with her life, she was "always in contact with the story".
"You can't get away from it. It is difficult," she said. "I don't know why this happened to him."
February 8 marked exactly three years since Gemballa was kidnapped from OR Tambo International Airport on his arrival in South Africa from Germany. His body was found nearly eight months later in a shallow grave in Lotus Gardens, Pretoria.
Gemballa had been suffocated, after his head was covered in duct tape and his killers sat on his chest to force the air from his lungs. His body was wrapped in a black plastic sheet before it was buried.
He had ostensibly come to South Africa to discuss a proposal to open a franchise of his business, Gemballa Sports Cars, which did tune-ups and luxury conversions on Porsches and Ferraris.
Gemballa had contacted Jerome Safi, a Krejcir associate, about the deal before he arrived in the country. According to someone who knew Gemballa well, he was excited about the business opportunity, as he was facing bankruptcy.
The source said that he was initially supposed to come to South Africa in October 2009, because "the new business partner in Johannesburg [Safi] put a lot of pressure on him to come". But he was only able to make the trip in February 2010.
Safi, who was interviewed by police, said in early 2011 that he had been in email contact with Gemballa about his South African trip: "I said to him 'I want to do a Gemballa franchise with you in this country. I have people ready to finance me'."
The funding, of up to R100-million, was going to come from Krejcir and slain Teazers boss Lolly Jackson. Their names were not disclosed to Gemballa, but Safi told the M&G there was nothing suspicious about this: "I didn't feel a need [to mention them] at that stage."
With abundant circumstantial evidence pointing to a wider murder conspiracy, it is unclear why the police have not made more arrests.
One reason may be the removal of Ludi Schnelle as lead investigator. Schnelle was taken off the case in November 2010 when a laptop seized during the investigation mysteriously vanished from his locked office.
The laptop belonged to Krejcir's business manager, Bulgarian national Ivan Savov, and allegedly contained information relating to Krejcir's financial dealings.
According to a February 2010 affidavit by Schnelle, Gemballa called his wife the night after he arrived in South Africa and spoke to her in English, which was strange, as they are German. He said he needed a million euros. She never heard from her husband again.
Police later traced the call to a cellphone, through pay-as-you-go vouchers purchased on behalf of a group of men, allegedly including Krejcir. The call to Christiane Gemballa was made from the phone six minutes after the airtime was recharged using the vouchers.
Christiane Gemballa said it had been "very difficult to find any results" as the investigation had petered out after an initial breakthrough at the end of 2010, when four men were charged.
Garlond Holworthy, Thabo Mogapi and Kagiso Linken were charged with Gemballa's kidnapping and murder and will stand trial in July. They have not yet pleaded. A fourth man, Thabiso Mpye, reached a plea agreement with the state in October 2010 after confessing to the murder and was sentenced to 20 years in jail.
The National Prosecuting Authority told the M&G that no "further arrests are expected at this stage". Gemballa said the laying of charges against the four men gave her little comfort because too many questions remained unanswered.
She said that the South African authorities had left her in the dark over the investigation. "From the beginning, the police didn't help me much."
Evidence collected by police earlier on in the case indicates that the four who have been charged were merely hired thugs. Mpye said in a statement to police in October 2010 that they were paid at least R25 000 each.
He referred to three other men named only as Madala, Kizzer and "the Bulgarian" who were complicit in the kidnapping and murder of Gemballa and have yet to be identified.
Mpye noted that: "Madala and Kizzer were very happy. They said that they were looking for this guy [Gemballa] for more than five years. I heard that they were communicating with him on the computer."
In September 2010 Mpye led investigators to Gemballa's body. He also pointed out the house in Edenvale, Johannesburg, where Gemballa was held before being suffocated.
The house was rented to Krejcir's financial manager, Savov, who claimed he was out of the country at the time and denied Gemballa was killed at his home.
There are several theories about the German businessman's murder and the reason why he was in South Africa. One is that Krejcir, who has been seeking asylum in South Africa since 2007, persuaded Gemballa to come to Johannesburg under the pretence of opening a conversion franchise with Safi.
A former business associate turned rival of Krejcir's, gold-refinery owner Juan Meyer, publicly claimed the Czech was using cars imported from Gemballa to smuggle cash into South Africa. Krejcir has vehemently denied this. He has also insisted that he had only briefly met Gemballa at a car show in Prague in 1995, but a source with knowledge of the German police investigation maintains the two men met in Prague in about 2002.
Meyer claims that he overheard an angry telephone exchange between them about money owed to Krejcir in September 2009. The phone conversation related to a Porsche imported in September 2009 and the fact that, when it arrived, the cash it was supposed to contain was missing.
In his affidavit, Meyer stated: "Radovan said that if Gemballa did not pay, he would get trouble." Krejcir has denied that he ever mentioned Gemballa's name to Meyer.
Krejcir previously told the M&G that he had legally brought R100-million into the country through the Reserve Bank in 2007, two years after fleeing the Czech Republic, where he faced charges ranging from fraud to kidnapping.
He denied involvement in Gemballa's kidnapping and murder. "I saw Gemballa once in my life for a couple of minutes at a car show in Prague in 1995.
"This is…the first and last time I saw him, not only saw him, even talked to him. But maybe it is the reason why I want to kill him, because I saw him 15 years ago?"
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