Schultz is in the end stages of disease and near death, as well as being in pain. Wilson is sitting at Schultz's bedside when House comes to see him about going to the medical conference. After Wilson speaks to House, Wilson goes back to reassuring Schultz.
Schultz dies while Wilson and House are away at the conference, and it is strongly intimated by House that Wilson gave Schultz access to his morphine pump to hasten his death. Wilson plans on using the case to admit to having assisted such access.