Updated

A Tennessee teacher charged with kidnapping a 15-year-old student and driving her to California had planned to take the girl to Mexico and took a boat from San Diego on a test run, according to federal court documents filed this week.

Meanwhile, the man who tipped off police to the missing pair is set to receive a $10,000 reward, USA Today reports.

CALIFORNIA TODDLER ALLEGEDLY KIDNAPPED BY 'DANGEROUS' FATHER

Griffin Barry, formerly of Brentwood, Tenn., said he was taking care of a remote northern California property when he encountered Tad Cummins with the girl. He added that the pair told him their names were John and Joanna and that they needed money for food, gas and a place to stay, ABC News' "Good Morning America" reported Friday.

But Barry, 29, said he became suspicious when the older man tried to keep the teen away. Police said with his help, they caught the pair last Thursday.

SUSPECT IN CHILD SEX ASSAULT HAD BEEN DEPORTED TO MEXICO

Barry will receive his award on Friday in Tennessee, USA Today added.

"The family owes each group, law enforcement, the media, and the public, a debt of gratitude that cannot be repaid," S. Jason Whatley, an attorney representing the girl's relatives, told Fox 17, adding that they would "step back" from the spotlight.

Cummins, who was the girl's teacher before being fired from his high school, is charged with taking a minor across states lines to have sex.

In carrying out his "audacious scheme," the 50-year-old Cummins switched vehicle license plates twice, disabled his vehicle's GPS system, used aliases, altered his appearance, paid only in cash and used back roads during his nearly six weeks on the run, according to the documents.

Cummins acknowledged in federal court in Sacramento on Monday that he was the suspect in the case and agreed to return to Tennessee to face charges there. U.S. Magistrate Judge Kendall Newman ordered him held as both a flight risk and a danger to the public.

Assistant U.S. Attorney Jason Hitt said Cummins was a danger in part for "using his position of trust as a school teacher" and for having two guns in the vehicle when he and the missing girl were found.

Assistant federal defender Ben Galloway argued the girl went willingly and that Cummings had no criminal history.

"These allegations do not involve force, threats or coercion," Galloway said.

"This was not an abduction or kidnapping as has been suggested," he added in an emailed statement. "He surrendered without incident and has been cooperative with investigators. He looks forward to returning to Tennessee as soon as possible to answer the charges against him."

Cummins still had the beard, mustache and glasses he had when he was arrested. He sat during the brief hearing clad in an orange jail uniform.

He offered minimal responses as he was advised of his rights and the charges that could send him to prison for 10 years to life.

Cummins left Tennessee because he was worried about an investigation into his relationship with the girl, the court documents said.

After taking out a loan for $4,500, court records said, the teacher took the money and two handguns and wrote a note to his wife saying he needed to go to Virginia Beach or the Washington, D.C., area to clear his head.

But instead of going to the beach, police said he picked up the student in Columbia, Tennessee, in his wife's car on the morning of March 13 and headed west.

"From the moment the defendant was suspected of his improper relationship in early 2017, he began plotting his escape with the juvenile victim," the records said.

The girl's father has told news media he believes his daughter was brainwashed.

Cummins also faces state charges of aggravated kidnapping and sexual contact with a minor.

Before disappearing, Cummins was investigated by the school system when another student reported seeing the then-married teacher kiss the girl at the Culleoka Unit School. Culleoka is about 60 miles south of Nashville near the Alabama state line.

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The Associated Press contributed to this report.