McQueary was a graduate assistant, and former varsity quarterback, when he happened upon Sandusky and the boy in a team shower late on a Friday night. He testified against Sandusky during the former assistant coach's trial in June that resulted in a 45-count guilty verdict.
Sandusky maintains his innocence and is appealing as he serves a 30- to 60-year prison sentence. Curley, Schultz and Spanier, who was charged late last year, all deny the allegations against them.
Through a school spokesman, Conrad declined an interview request Friday, and McQueary attorney Elliot Strokoff did not return a message.