Thanks, Mr. Acer, that makes sense! Looking back, there were two parts that I tripped over:
My first hang-up was the sentence, "Because of our secret preparation, we know for sure that the colors they saw on the cube are white, red, and green." I had interpreted this incorrectly as "we know for sure that the colors they SELECTED on the cube are white, red, and green." For the example used in the article, the performer doesn't know if the selected colors are red-white-green or red-red-green. (Not that it matters in the end, as you have noted.)
The second thing that I got hung up on was the bluff revelation. The example bluff mentioned in the article works for the given situation, but cannot be blindly used for all color combinations, which was my assumption. You cannot simply name any two force colors and a non-force color and necessarily have the bluff revelation work as intended (i.e. fail), assuming the ladies all keep their eyes closed. Some thinking on your feet is evidently necessary for this routine.
I'll stop now, my head hurts. I think next time I better stop reading and answer the phone... ;-)