Read what he writes elsewhere at Mudcat, then read between the lines of Dick Greenhaus' post. There are three possible conclusions:

1) The "O Brother, Where Art Thou" soundtrack is not available through Camsco;

2) Dick Greenhaus somehow holds the soundtrack musicians of "O Brother, Where Art Thou" accountable for Bob Dylan going electric at the 1965 Newport Folk Festival;

3) some combination of 1) and 2).