Its report conflicts with the government's contention that there are no remaining missing people from the attack on the Westgate Mall and suggests the death toll could still rise as investigators dig through the rubble.
Abbas Gullet, head of the Kenyan Red Cross, said: "The only way to verify this is when the government declares the Westgate Mall 100% cleared - then we can resolve it."
The Red Cross number has been dropping over the past week as bodies have been positively identified and as some missing people have been reunited with their families.
On Sunday, interior minister Joseph Ole Lenku said police had no missing persons reports from the attack and did not believe there were any hostages in the mall building when it partially collapsed. He left open the possibility, however, that things might change.
Investigators from Britain, Canada, the US and Germany, are helping in the investigation into the attack in which six Britons died and are aiding Kenyan forensic experts poring through the mall complex.
Results are not expected until later this week at the earliest.