Ron always just fucking knows
If you remember, Ron was always weirdly good with Divination. Whenever he’d joke about a possible outcome, it would eventually happen in some roundabout way!
There’s actually a whole point about this in these Harry Potter analysis books I used to read obsessively. Two of their cardinal rules of HP foreshadowing are “Hermione is always right, except when she’s emotional” and “Ron is always wrong, except when he’s joking”. This actually plays out pretty frequently in the series if you look for it!