Authorities had several false alarms Sunday, when they dug into portions of the building's foundation to investigate readings by ground-penetrating radar.
The area remained cordoned off with crime tape as officials used ground-penetrating radar, extracted soil and walked police dogs around the businesses and parking lot on Monday.
By Monday evening, workers had excavated a roughly 5-by-5-foot hole in the floor in the Sara Lee Bakery Outlet.
But by 11 p.m. Monday, officials said it was likely that they would discontinue the search if nothing was found within a few more hours because many of the workers from other areas had to return to their jobs.
Robinson had said earlier that "we've made a promise that we're not going to leave here without this answered. What that answer might be, I can't say."
Orange County authorities had been confident that Ashani's body is buried at the site, he said.
Florida authorities had received a credible tip from an unnamed source that the body is at the site, Robinson said Sunday.
Ashani was 4 when she disappeared in 1997, but authorities believe that she wasn't killed until 1999.
When she disappeared, the girl was in the care of her grandparents, Kaia and Ernest Jackson, who were fugitives in a 1988 New Jersey child-abuse case.
The Jacksons eluded capture for 12 years before they were arrested in Tulsa in 2000, the World has previously reported. They lived under the aliases Butch and Naomi Hill while in Oklahoma, and they homeschooled their four children.
After their arrests in Tulsa, detectives from Bergen County, N.J., said Ashani's mother, who lived in New York, sent the girl to Florida for a visit with her grandparents two years earlier and hadn't seen her daughter since, the Tulsa World reported in 2000.
The Jacksons reportedly came to Tulsa from Florida shortly after refusing to return their granddaughter to her mother.
They assumed new identities for themselves and their children, as they had done in numerous other U.S. cities since they were charged in 1988 in New Jersey, authorities said 12 years ago.
The couple had been sought since their son Cymande Jackson escaped from their home in Teaneck, N.J., on June 24, 1988, and wandered into a restaurant, where patrons reported seeing horrific scars, burns and other injuries covering most of his body.
The boy was taken into protective custody, and the Jacksons were arrested in New Jersey, but they posted bail and fled with four of their other children, the World has reported.
After their arrests here, the Jacksons were convicted of aggravated assault and child endangerment in New Jersey.