"Just add the kiwi in at the end of the jello setting up, especially if you don't mind the "mixed" look of the jello, or just on top after it sets.
Maybe Sandra has a trick to getting it to set up that did not get mentioned in the recipe. That happens on here, those recipe "adders" don't always add all the information so it could have been left out.

"Very Tasty! My children and I love this recipe. On the show she did say to use the fork every hour to scrape and keep it in a shaved ice form, and it does work. I could not find the papaya in my town so we use guava or some other fruity flavored juice (usually in the mexican section of the grocery store). It is still just as yummy.