The Senate report is very clear about this. The trip was initiated in response to a query by Cheney's office, not by his wife. He was selected to go on that trip by people other than his wife as well.
Inotherwords incompetent nepotism is not an accurate description of what happened.
His wife was in no position to initiate anything. But for purposes of this controversy, she did recommend him for the trip. Cheney was allegedly told by a high-ranking CIA official that Wilson's wife recommended him for the trip. And at least that appears to be true.