Kaul, an additional SP of the CBI, had earlier told the court that he wanted to file a charge sheet but his two senior officials favoured filing a closure report.
The court later rejected the closure report and summoned Rajesh and Nupur Talwar as accused in the case.
Concluding his testimony as the last prosecution witness in the case, Kaul on Wednesday said it was clearly mentioned in the report that Rajesh and Nupur were in the crime together.
Kaul had told the CBI court on Tuesday that Rajesh killed his daughter Aarushi and domestic help Hemraj with a golf stick and a sharp-edged weapon after finding them in the same room.
Fourteen-year old Aarushi, daughter of the dentist couple, was killed at their Noida residence on the night of May 15-16, 2008. Hemraj's body was found on the terrace a day later.
Accusing the Talwars of attempting to misguide the probe, Kaul negated the theory that murder could have been committed by Hemraj's friends -- Krishna, Rajkumar and Vijay Mandal.
Kaul said Talwars wanted the CBI to carry out LCN DNA test - a specialised test not available in India -- on some items seized from the crime scene. The test was not done because the Centre for DNA Fingerprinting and Diagnostics and Centre for Cellular and Molecular Biology were of the opinion that said since DNA testing of the samples was done, the test asked by Talwars needn't be conducted.