The Coast Guard investigated Patrick McDermott's disappearance and determined he fell overboard during a fishing trip off the California coast.
E! News said a team of private detectives hired by "Dateline NBC" found the Korean-American lighting technician in Mexico after following his moves on the Internet.
"Mr. McDermott's wishes, according to his counsel, is not to be 'hounded' any longer by investigators or the media," lead investigator Philip Klein told reporters at a press conference.
It is unclear what criminal charges McDermott may now face.
McDermott and Newton-John dated for nine years before breaking up shortly before his disappearance amid reports he was suffering dire financial problems.
The singer reportedly declined to comment on the story.