Putting Ivanka Trump at the same odds as for Michelle Obama looks like a joke to me. I mean, Michelle Obama has really some chances of becoming the next president, while Ivanka has none. The only explanation for me is Ivanka's admirers placing those bets just to see her in that list.
Both Michelle and Ivanka have zero chances for 2024. In all probability, the Democratic nominee for 2024 would be Kamala Harris (if she doesn't become the president before 2024). Right now it is difficult to predict who will be the Republican nominee, but I don't think that someone like Ivanka who has achieved very little so far has any serious chances.