So I hypothesize that what really matters is not divorce rate, but happy marriage rate. Unfortunately that data is not in this study. And furthermore, if it was, I would suspect significant bias. In the church world that I was a part of there was significant pressure to keep up appearances. So I don't think you would be able to trust either the married persons' self assessment of happiness nor the external assessment of the people who know them.
With this new metric in mind, I went back and re-thought the logic in each of the OP's significant predictors. First stop, "How much money you make". IMO this one falls flat on its face. It's easy to imagine situations where someone would stay in an unhappy marriage just because their partner has money. It's also easy to imagine situations where someone makes a lot of money, but stays in an unhappy marriage because their partner would get half of it in a divorce. Another factor that I think is suspect is "How many people attended the wedding". When a lot of people saw you get married it seems like there might be more pressure to stay in an unhappy marriage to save face to all the people who attended your wedding. I'm a little bit less confident about the reasoning here, but it still seems plausible.
The rest of the predictors seem reasonable to me, especially "How long you were dating". This one stands up under the happiness test and just seems to make sense, provided that the extended dating years were as similar as possible to the married years, minus the marriage license.