She says she had no indication he could be a killer, but now she feels she was lucky she wasn't hurt.
"I didn't think he was violent, but as time goes by, especially now, I think he was," said Granadillo. Granadillo says that just days before van der Sloot allegedly killed Stephany Flores, van der Sloot asked her for money to return to Aruba.
Van der Sloot is now being held in Peru's notorious Castro Castro Prison in a spartan cell. Sources say the 6-foot-4-inch Dutchman is not granting interviews unless he is paid, but the prison did grant ABC News access to van der Sloot's cell. His bed is a mattress on a slab of cement; his sink and toilet are little more than a hole in the floor.
He is being isolated from the other inmates for his own protection.
"In these prisons, you can get drugs delivered any time of the day or night to your cell, so people come in and out and if someone has been given money as part of a contract to get rid of Joran van der Sloot, they're going to get him," said Michael Griffith of the International Legal Defense Council.
A judge is expected to interrogate the Dutchman next week about Stephany Flores' murder.
Court officials said in a statement that Judge Carlos Morales will travel Monday to the prison where the 22-year-old suspect is being held.
His questions will focus on the May 30 killing of Flores. Chilean police say Van der Sloot has confessed to killing the Lima woman.
Thursday's statement said Morales will pass along any information to pertinent authorities if Van der Sloot discusses the 2005 disappearance of Natalee Holloway, a case in which he also is the prime suspect.
Van der Sloot has said he is ready to talk about the case, but only to Aruban authorities.
The Associated Press contributed to this story.