By Robbie Owens

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DALLAS (CBSDFW.COM) – Relatives of a missing Dallas woman are now openly wondering why her estranged boyfriend appears to have vanished, as well.

Marisol Espinosa never arrived at her job at North Park Center last Tuesday.

Faustino Valdez told police that Espinosa kissed him goodbye before she left. Over the weekend, he joined family and friends in a hastily arranged search of a wooded area in the Pleasant Grove neighborhood. Her SUV was recovered at an apartment complex nearby with her purse and belongings locked inside.

Meanwhile, some experts believe the complex could be full of potential witnesses—but, evidence does not get better with time.

“If you don’t get it quick: it’s lost,” says John Rosa, CEO of EJR Agency. A licensed private detective, Rosa has more than three decades experience finding people who don’t want to be found. He says police must move quickly. “I think that within 24-48 hour period, there should have been somebody out there talking to those folks,” says Rosa. “You get witnesses that maybe saw a Caucasian individual… and a week later, maybe the guy is black maybe. It changes that much!”

Meanwhile, family members tell us that Valdez was questioned by police. But, detectives have declined to call him a suspect. Relatives say he has not been seen since earlier in the week.

“That’s not a good sign,” says Rosa. “Folks that don’t have anything to hide… I’m not going to run and hide.”

The apartment complex where the SUV was found does have surveillance cameras and any evidence they may have captured has been turned over to police. Witnesses are still being asked to come forward.

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