It might assist if I set out the co-ordinates for each of the four waypoints;
(1) Williams Field - 77.53S 166.48E
(2) NDB - 77.51S 166.41E
(3) Somewhere in
McMurdo Sound - 77.53S 164.48E
(4) TACAN - 77.53S 166.58E
If the Nav officers were telling the truth, it was still a monumental balls-up.