The manhunt for the fugitive husband of a Bronx daycare owner charged in the drug-exposure death of a toddler has expanded to the Dominican Republic, federal law enforcement sources told The Post Monday.

Cops have been searching for the husband of Grei Mendez De Ventura since 1-year-old Nicholas Feliz Dominici died from suspected fentanyl poisoning at her Divino Niño Daycare – with the Regional Fugitive Task Force now following up leads inside the couple’s native country.

“We’re all working together to find him – nationally and over in the Dominican Republic,” the source said.

Mendez, 36, and accused cohort Carlisto Acevedo Brito, 41, her husband’s cousin, were charged with murder, assault and child endangerment on Sept. 16, one day after Nicholas and three other children were found critically ill at the childcare facility — described by authorities as a front for a drug-peddling operation.

Mendez’s on-the-run husband was described by police sources as “the main player” in the alleged drug-selling operation at the basement day-care center.

Authorities have not identified the fugitive by name.

Meanwhile, Mendez’s attorney claimed that cops have the wrong person in custody.

“She’s paying for somebody else’s crime, basically,” lawyer Andres Manuel Aranda told Gothamist.

“You know, this lady doesn’t fit the profile of a drug dealer,” Aranda said. “She had $100 in the bank, from what I understand. She was keeping down two jobs, not necessarily someone who’s out there dealing with a kilo weight.”

He said Mendez’s own child was enrolled at the daycare, and would’ve been in harm’s way as well had he not been taken on a trip by a relative that day.

“She’s distraught about what happened with the children, especially Nico,” Aranda said. “She feels that she’s being held unjustly.”

Federal and local law enforcement sources disputed that claim, however, saying Monday that Mendez’s 2-year-old son was himself exposed to drugs last year and treated without police being summoned. The boy had allegedly been kept away from the day-care center after that incident, the sources said.

“She purposely kept her son away from the center after almost losing him after he was exposed to drugs,” a source alleged.

Aranda didn’t immediately return a request for comment Monday.

Prosecutors said Mendez made several calls, including two to her husband, before calling 911 after she found the toddlers unconscious around 3:30 p.m. on Sept. 15.

The three other sickened kids — a pair of 2-year-old boys and one of their 8-month-old sisters — were saved with the overdose-reversal drug Narcan, Mayor Eric Adams said last week, but Nicholas was pronounced dead.

Mendez – who along with Brito also faces federal drug charges – is suspected of deleting more than 21,000 messages with her husband dating to 2021 before turning her phone over to cops, according to court documents.

Authorities said they uncovered a kilo of fentanyl sitting on mats the children slept on, according to court papers. They also seized several “kilo presses,” which are usually used to combine the drug with cocaine or heroin.

Last week, police said they found an additional cache of drugs hidden under a trap door at the Kingsbridge building.

Mendez’s ex-husband’s family also told The Post over the weekend that she duped him into a sham marriage to get into the US from the Dominican Republic.

Federal and Bronx prosecutors said they’re confident they’ll eventually catch up with her new husband.

“We’re going to get him,” Assistant US Attorney Damian Williams said last week. “Look out for more on that soon.”

Additional reporting by Ben Kochman