"There was no apparent panic," Rosenthal said in a statement.
Witnesses have said the EMTs told workers to call 911, then left when they were asked to help the 25-year-old pregnant woman.
Rennix, who also was the mother of a 3-year-old boy, died at a hospital shortly afterward. The cause of death has not been determined. Her baby did not survive the premature birth.
Rosenthal said Jackson, a four-year veteran, was asked by an employee to summon an ambulance because the six-months-pregnant Rennix was showing asthmatic symptoms and was experiencing abdominal pain.
Rosenthal said Jackson radioed for an ambulance and she and Green, a six-year veteran, stayed until they knew help was coming.
"They were thanked by the employee for their response," he said.
Rosenthal said "protocol, training and regulations" also kept the two emergency workers from intervening further because they didn't have any equipment or medications and worked as dispatchers rather than in the field.
Green and Jackson have been suspended without pay. They are also under investigation by the Brooklyn district attorney's office and the state Department of Health, which oversees EMT training.
A union covering emergency workers has said that all dispatchers are required to be field-trained EMTs or paramedics in order to be more effective at their jobs, and are capable of getting involved in emergency situations. The New York Fire Department says all members take an oath to help others whenever emergency medical care is needed.
Cynthia Rennix said the story doesn't match what she was told by her daughter's coworker and supervisor.
"They were well aware of the seriousness of her being on the floor. They should have at least looked to see what was going on," she said Thursday. "That's no excuse for it."
Medical Examiner's Office spokeswoman Ellen Borakove said Rennix's body would be exhumed and an autopsy performed. The results will be released to authorities investigating the case.