I don't know how much credence you can lend to this report. According to the article, there was a recording of Anna Chennault's calls that she tells the ambassador to "just hang on through election". If this is true, why wouldn't this recording be in the article? They had no trouble putting LBJs calls in there. Do you really think LBJ would have sat on the evidence? Where is the evidence? My guess is that it simply doesn't exist.
As I recall, LBJ was quite aware, but for some sort of personal reason didn't use it against Nixon. The book I have with that is at home, so it's not like I can give you anything solid right now, as I'm on campus.
LBJ hated Humphrey's weak campaign against RFK and apparently viewed him as too weak to be President. He was rooting for Nixon in private, IIRC.
