Suspect in Holloway Case Allegedly Caught Arranging for Sex Workers

On the tape, van der Sloot told van der Eem that Holloway suffered a seizure during a romantic encounter between the pair, who had met hours before at a local nightclub.

At another point he told van der Eem, "I tried to shake her. I was shaking the bitch. I was like, 'What is wrong with you man?' I almost wanted to cry."

Van der Sloot said he felt lucky the police were not able to recover Holloway's body.

"I think I am incredibly lucky that she's never been found because if she had been found I would be in deep [excrement]," van der Sloot said on the tape.

De Vries dismissed van der Sloot's claim that he was lying on the tape or that drugs affected his statement, saying, "I don't buy these allegations."

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Instead de Vries said the only question that remained was the identity of "Daury," the "really good friend" whom van der Sloot said he called from a pay phone and who he said helped him dispose of Holloway's body.

"Our insider was pushing him the next day [after the taped confession] a little bit on the name; and then he came up with 'Daury,' but the name he mentioned is not the Daury in the news," De Vries said.

Van der Sloot's attorney, Joe Tacopina, said there's evidence to suggest the pay phone call never happened. Tacopina said the Aruban Coast Guard checked the pay phone that Joran talked about on the tape and found no such call, which would apparently give credence to van der Sloot's claim that the story he told on the tape was a lie.

"The Aruban Coast Guard has already looked at that pay phone. There is no such call," Tacopina said.

But de Vries said Aruban investigators told him it was not possible to for them to determine if the call was placed.

"I don't know how [Tacopina] knows this, because I had a telephone call a couple of months ago; saying it's impossible to say," De Vries said. "Maybe he is the same like his client and made some things up."

Aruban investigators have yet to publicly weigh in on recent developments in the case.

Some say that De Vries' methods, namely the fact that he used van der Eem to gain van der Sloot's confidence and videotaped him unknowingly, crossed a journalistic line. But he said he had no regrets.

"We did what we had to do, and what we accomplished is that the investigation is reopened and that Joran is again a suspect for homicide. Before this Joran considered himself as a winner," De Vries said.

Investigation Reopened

If van der Sloot's own words are to be believed -- his fears about the body being found, and his calling a "really good friend" instead of an ambulance -- then his story raises questions about the identity of his friend with the boat, Daury, and the possibility of that pay phone call.

ABC News' Elizabeth Vargas caught up with Daury Rodriguez, a 21-year-old Aruban man and longtime friend of van der Sloot's, in Aruba in February. Rodriguez denied that van der Sloot had called him or that he was with van der Sloot on the beach the night Holloway disappeared.

"So when Joran Van der Sloot said he had a friend named Daury who was here on the beach May 29, 2005, it wasn't you?" Vargas asked him.

"No," Rodriguez replied. He also told Vargas that van der Sloot apologized and said in an online conversation that he'd lied.