The suspect, Mary Nekesa Ambani had been accused alongside Timothy Omondi of carrying out the murder of the Dutch tycoon and a night guard in his apartment in Shanzu in early June.
The two suspects were presented before Mombasa resident judge, Eric Ogola in order to face murder charges.
State counsel Vallerie Ongeti, however, informed the judge that the Director of Public Prosecution Noordin Haji intended to convert Ambani from a suspect into a key witness.
Ongeti also requested the court for the two suspects to be remanded in separate prisons after the new development. The two had been arrested after Ksh3 million, stolen from the Dutch tycoon, was traced to them.
Police officers privy to the investigations pointed out that both Ambani and Omondi had invested the money and also built a mansion in Kiemebeni, Mombasa.
Other funds were used to furnish the mansion with house items such as a television, refrigerator, radio system, solar system among others.
Police also accused Rouwenhorst’s wife Riziki Cherono of hatching the scheme that eventually led to his death.
The detectives pointed out that the perpetrators of the crime knew the crime scene very well, hence their easy access and movement within the premises despite a tight security system.
The accusations were, however, disputed by Cherono who claimed that she was the proverbial scapegoat in the murder probe.
“I am a scapegoat to save face by investigators. I maintain that the charges against me are a product of pressure by the public and the Dutch authorities to show that they are working to solve the murder,” she previously stated.