James Fletcher is absolutely a skeptic when it comes to Divination, so might poke fun. But Leo could one day See something linked to Jimmy eventually finding out about his upper-class parentage, and Jimmy would still think that was absolute rubbish. xD

I don't know how well-known his abilities are in society in general so not sure how or why exactly Savino Zabini would find out, but he is interested in meeting any and every seer... though I don't know if he actually knows how to interact with small children xD