It predicts likely winners based on the round of 32 performance (plus prior data). That's still "prospective" with respect to the finals
Yes. I don't like phrasing this as being prospective for the World Cup as a whole. It's for the knockout stage. (Which the abstract says! But the title doesn't.)
Which is very reasonable. You estimate odds after seeing teams playing with the actual squad selection at that period in time. Otherwise I'd dismiss the predictions as lucky guesses in a row.