"I thought I was going to die," said the former Tampa Bay Buccaneer, who says police thought his cellphone was a handgun.
The woman's remains were found in December 2017 along Interstate 75 in Butts County.
The teen left a message for her parents saying she and her boyfriend are going to Arkansas, authorities said.
The teacher, who has been at the school since 2004, teaches social studies and also does the play by play for the football team, police say.
The men have to pay a total of almost $1.4 million in restitution.
Someone in the crowd became angry and opened fire after the two men climbed onstage between performances, Atlanta police said.