"Don't shoot her in the face please," Morrow allegedly says on the secretly recorded tape, which was played in a court hearing this week.
At a probable cause hearing on May 7, Judge Barry Tatum ruled that there was enough evidence to send the case to a grand jury, which will decide whether to indict Morrow, Bland and Joshua Stubblefield.
Police say Morrow and Bland offered Stubblefield $150,000 to kill Stribel, who has continued to be supportive of her daughter.
"I love her dearly," Stribel told ABC News.
Stribel declined to comment further, saying, "We both have Mother's Day this weekend. We need a little time for healing."
Police said Morrow and Bland, who were arrested in November, wanted to collect what they believed would be $2 million in insurance.
"You can have a closed casket. You just got to make it look like a robbery though, you know what I'm saying?" a male voice on the tape says.
Stubblefield wore a wire during the exchange, authorities said.
Wilson County Sheriff Terry Ashe told WKRN News 2 that he believes the trio would have gone through with their plan. "If we hadn't intervened, I feel certain this would've been carried out," he said.
Morrow's lawyer, Jack Lowery, told ABC News the conversation was "not something that's palatable or acceptable," but insisted that Morrow had not committed a crime.
"There was never an agreement" to kill Stribel, he said.
"Kids sit down and talk about things and never follow through with it," he said. "It's the thrill of talking about it. They get ideas and then they start talking about it."
Lowery said Morrow, who is free on bond, is still living with her mother and that Stribel is "totally supportive of her. She sincerely does not think her daughter could have ever done that."
Assistant District Attorney Brian Fuller declined to comment.
"I think it proves that a mother's love for her child is just extremely overwhelming, in this case, blinding," Ashe told WKRN.