Short answers, pulled from the story.
James Dallas Egbert III was an American student and child prodigy who enrolled at Michigan State University at the age of fifteen. Born in Dayton, Ohio, on the 29th of October, 1962, he disappeared from campus in August 1979 at the age of sixteen. He died on the 16th of August, 1980.
Egbert left his Michigan State dormitory on the 15th of August, 1979, after writing a suicide note and entering the campus steam tunnels. He consumed methaqualone intending to die, survived, and then went into hiding at a friend's house rather than return to campus. His personal file documented depression, loneliness, parental pressure, and drug addiction.
No. Private investigator William Dear publicly linked Egbert's disappearance to Dungeons & Dragons, but the connection was speculative and false. Egbert had entered the campus steam tunnels to attempt suicide, not to play a game.
William Dear was a private investigator hired by Egbert's parents on the 22nd of August, 1979, to search for their missing son. He publicly amplified theories linking Dungeons & Dragons to the disappearance, then located Egbert and returned him to his family on the 13th of September, 1979. In 1984, Dear published The Dungeon Master: The Disappearance of James Dallas Egbert III through Houghton Mifflin.
The case drove the Dungeons & Dragons Basic Set from roughly 5,000 copies sold per month to more than 30,000 per month by the end of 1979. The nationwide media coverage made the game's name familiar to a public that had largely not heard of it before. The controversy also inspired works such as the novel and film Mazes and Monsters, which deepened public attention on the game through the 1980s.
Egbert was admitted to Grandview Hospital in Dayton, Ohio, on the 11th of August, 1980, with a self-inflicted gunshot wound. He was seventeen years old, and his parents were told he had no chance of survival. He died on the 16th of August, 1980; hospital spokesman Max Peterson confirmed the death at 10:30 that evening.