Just found the answer to the question of how Grogan died:

â??Emmett's road petered out 'at the end of the line' of the Coney Island subway April Fools Day 1978--some twelve years later, where his body was found, dead of an overdose. Even in death he was charismatic. The detective who found his body said, â??I took one look and said to myself, â??This is somebody.â??â?
From Playing for Keeps, By Peter Coyote


http://www.diggers.org//freefall/forkeeps.html