Boyfriend of American Woman Found Dead in Mexico City Airbnb Shares Final, Fearful Messages: 'I'm Shaking'

The boyfriend of an American woman who died inside an Airbnb in Mexico City, where she was vacationing with friends to celebrate the Day of the Dead, has opened up about their final conversation.

Victor Day, 30, began receiving text messages from his girlfriend, Kandace Florence, 28, early Sunday morning at about 2 a.m., he told PEOPLE in an interview on Wednesday.

"Everything was good. She just said that they were out, they were drinking, everything was fine," he said.

Day said he saw on his girlfriend's Instagram stories that she was out at what appeared to be a rooftop bar with fellow travelers Jordan Marshall, 28, and Courtez Hall, 33. They appeared to be drinking wine, surrounded by plants as the Mexico City skyline shone in the background.

Hours later, the three friends from Virginia Beach were found dead of suspected gas poisoning in an Airbnb they'd rented in the La Rosita neighborhood of the Mexican capital.

courtesy Victor Day

Mexico City authorities told Spanish-language paper El País they've opened an investigation into the incident and that they believe the American visitors died of "carbon monoxide poisoning."

A rep for Airbnb did not immediately respond to PEOPLE's request for a comment.

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In a text message sent about two hours after she indicated that everything was fine, Day told PEOPLE that Florence said she was "tired" and feeling very emotional.

"I write her, 'What's wrong?' and she says, 'I'm just not okay. I wanna go home,'" Day said. "And I write her, 'You're not enjoying it. What's wrong though?' She says, 'I feel drugged.' And I say, 'Where's Jordan? Are you home or out?'"

Florence said she had just returned to the Airbnb, Day continued. Although she told him that she hadn't taken any drugs, she said that because of the symptoms she was experiencing, "I feel like I took Molly," a reference to the drug ecstasy.

"I'm literally in pain," Florence said, according to Day. "I'm like, shaking."

Day asked if it was possible someone slipped something into her drink while she was out with Marshall and Hall, warning her, "If you didn't watch your drink the whole time, you may have gotten drugged."

"Her last text to me was, 'I wasn't complacent,'" Day said of the text he received at 4:47 a.m.

"Three minutes later, she FaceTimes me," he continued. "And that's when I clearly see she's vomiting. She's been crying. I mean her whole face was wet, crying or vomiting or maybe she splashed water on her face."

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Day said the conversation continued before he dozed off for "probably about five, 10 minutes." When he woke up, their phones were still connected.

Courtesy of Marshall Family Kandace Florence, left, and Jordan Marshall in costume at Day of the Dead festivities

"But now the phone screen is pitch black as if she put the phone down or the phone fell. But the camera side is facing the ground," he told PEOPLE. "So I don't see anything. But I could hear something going on in the background and I put the phone to my ear, and it sounds like her vomiting or dry heaving, or both."

Day said he recalled telling himself, "Everything's going to be okay." He believed if she'd been drugged, throwing up and then sleeping it off would help.

"She'll go to sleep. She'll wake up the next morning and she'll tell me all about what could have happened," he remembered thinking. "And so that to me is what eats me up. Because knowing that I could have helped a little bit more, knowing that at that moment I probably could have called the police. I could have done something but instead I went to sleep."

Courtesy of Marshall Family Jordan Marshall and Kandace Florence in Italy

The next morning, Day checked in with Florence via text. "How are you feeling? Is everything okay?" he wrote. "About 30, 45 minutes pass, I don't get anything. And I started to think, I was like, Well, it seemed like she did have a night. She's probably just oversleeping."

After another hour passed, he said he started to worry. "Something definitely wasn't right," he recalled thinking.

"And then that's when it clicked," Day added. Florence had shown him the Airbnb listing a month before her trip with Marshall and Hall, so he used it to contact the host.

"Something is terribly wrong. I need someone to check on the apartment," he said he wrote to the host through the site. "And we go back and forth for a little bit and eventually she tells me, okay, she's sending her security into the apartment."

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Day said that 10 minutes later the host wrote back, "saying that they found all three of them in the apartment unresponsive without vital signs" and that emergency services were contacted.

On Monday morning, Day heard from the host again. "She tells me that they were all pronounced deceased," he said.

"I refused to believe that they were dead. It seemed so surreal, it didn't feel real," he said. "And so I began to ask her, I'm like, 'Did the police do anything? Did y'all, did they try in Mexico to save their lives?' And she assured me. She was like, 'Oh, of course. Of course, they tried. And unfortunately it's just, it's too late. They've all passed.'"

FaceBook (L-R) Jordan Marshall, Kandace Florence, and Courtez Hall

Day said he was sure the Airbnb listing said the rental had carbon monoxide detectors but wondered if they were not working.

Florence, who would have turned 29 Thursday, was supposed to head to D.C. to celebrate her birthday with him, according to Day, who is now planning to visit Virginia Beach to be with others who loved her.

"It's tough," he said. "But I know Kandace is looking down and trying to give me the strength."

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Florence was the owner of a company called Glo Through It, which makes candles with inspirational messages.

The Make(HER) Collective — a group of local women makers and business owners from the Hampton Roads area — is now seeking donations via GoFundMe to establish The Kandace Florence Memorial Scholarship and help Florence's family with funeral expenses.

"We can't imagine our community without her, and we know the world had big things in store for her," the group said. "But not because she was given it — because she worked tirelessly for it. While still prioritizing self-love, rest, fun, and family."