Espinoza told WSVN that all data gathered in the case shows the body is her's, but officials are waiting to compare the fingerprints with Federal Bureau of Investigation records.
Stefaniak's family also said they are not done fighting for her, saying they plan to continue to press authorities to look into the possible involvement of more people in her death.
Stefaniak left Fort Lauderdale on November 22 to Costa Rica with her sister-in-law, April Burton, on a girls trip.
Costa Rican authorities say they found what appears to be blood in the Airbnb apartment rented by a missing South Florida woman who was on a vacation to celebrate her 36th birthday, and that prompted a search that led them to a still-unidentified body discovered outside.
Espinoza shared no details on what police uncovered, other than to say they have reviewed surveillance footage and interviewed anyone they could find who had contact with Stefaniak.
Stefaniak, a 36-year-old from Hallandale Beach, Florida, missed her flight home last Wednesday, and her family has been searching for her ever since.
Stefaniak was supposed to return home from her birthday trip on Wednesday.
"Stefaniak dropped Burton off at the airport in San Jose on November 27 and returned their rental auto". However, her body found near the hotel suffered blunt force trauma and had a bruise on her neck. Before the call dropped she said to him, 'I'm thirsty.
Carla Stefaniak went missing on November 28. Authorities have yet to confirm if the body of the femaly found in Escazu is the disappeared tourist
Her family said they are skeptical of that story, however. She Facetimed a friend in NY, telling him she was going to ask the security guard to buy her a bottle of water. She continued with, "it's pretty sketchy here", according to Burton. He was taken into custody late Monday evening after investigators said he was providing conflicting statements about his story and that his story in question didn't match up with security footage. However, an Uber driver she scheduled to pick her up still showed up at 8:30 a.m. Jaime said.
That same night, she was Facetiming with a friend in NY when the call dropped about 9pm.
The suspected murder is a nightmare for Costa Rica's tourism industry - its main source of income.
On the eve of her departure, she texted Ms Burton to say it was raining hard and there was a power cut at the property. Authorities confirmed that the body was likely Stefaniak shortly after.
"So we don't know if it's the guards, we don't know if it's the Airbnb guy, we don't know if it's both", said her sister-in-law April Burton.
"You can't imagine what we are feeling", said Carlos Caicedo, Stefaniak's father.
CNN affiliate WFTS reported that a lawyer for the place where Stefaniak was staying said the facility is temporarily closed.
According to authorities, investigators raided his apartment, Apt.