CORAL SPRINGS, Fla. -

[This is Part 2 of a two-part series, click here to read Part 1.]

After two Coral Springs police detectives told their supervisor they were convinced that Gustavo Enamorado Dubon, who was jailed on a first-degree murder charge in the murder of businessman Francisco Cuevas, was innocent, a question hung in the air.

What would they do with the information?

Initially the supervisor, Sgt. Ryan Gallagher, seemed to want to simply let the case take its course.

"Listen, I'm not suggesting that anyone fabricate anything," Gallagher said to the detectives, David Young and Brian Koenig. "I’m not suggesting that anyone stretch the truth. If he can get off, then he can get off. I mean, that's what the criminal justice system is for. That’s what defense attorneys are for."

They discussed taking the "problems" to assistant state attorney Gregg Rossman.

"It’s Gregg's job to do what he has to do with the case," Gallagher said.

So when did they go to Rossman about their concerns that Dubon was innocent?

"A month ago they did speak with them and told them here are some concerns that aren’t adding up," said Coral Springs police spokeswoman Carla Kmiotek.

The tape was made in April of 2013, and only surfaced last month. That means roughly 15 months passed -- all of it with Dubon sitting in jail. But Rossman said he was aware of the detectives’ reservations all along and that they have no bearing on the case anyway. And though he concedes the audiotape is "extraordinary to hear," he said it means nothing.

"That audiotape has zero effect on the Dubon case," said Rossman, adding that it was only opinions and those aren’t admissible in court.

But don't the detectives' opinions hold weight?

"The detectives' opinion of a case holds no weight," said Rossman. "The evidence holds all the weight."

But that's exactly what the detectives said the case lacks – evidence. They pointed to contradictions in Dubon’s testimony. They believe he was fed all the information that was contained in his now recanted confession -- the fact that the body wasn’t found where he said it would be, despite $30,000 spent by the city on excavation and lake draining in search of it. They also voiced concerns that he was led to confess by other investigators in the case and did so in a bid to keep from being deported away from his fiancee and child back to Honduras.

"He was trying to stay in the country or become a hero," said Young on the videotape. 

Dubon was never considered the main suspect, and speculation has always centered on Cuevas' business partner in his metal shop in Pompano Beach, Hagen Christ, who has not been charged in the case. The detectives indicate on the tape that Dubon claimed the murder was a hit involving Christ and carried out by the notorious MS 13 street gang, but the information he gave on alleged cohorts was contradictory.

"[Dubon] gave four or five different versions of the names, tattoos," said Young.

"Buddy, it is MS 13, he ain't giving them up," said Gallagher.

The big fear for the investigators was that the focus on Dubon could kill any chance of catching the real killers, with the detectives saying that if they’ve been "barking up the wrong tree for months" the investigation is severely impaired. That’s a concern shared by Rossman.

"That’s exactly what we’re here for," said Rossman. "We never want to prosecute the wrong guys."