I have an adult student who's just started this piece, and because I liked it, I bought online a second-hand copy of the book it comes from, Mini-Jazz by Manfred Schmitz.
At the end of the preface, the composer says "By the way, there's another very important thing to remember in playing jazz: all eighth-note groups should be played as triplets" and then goes on to show examples of the crotchet-quaver and three-quaver patterns typical of swung quavers.
I do wonder if those who set the exams this year had actually read this introduction. Of course it's a sweeping statement, but just because he doesn't add that "equation" at the beginning of the piece that signifies swung quavers, doesn't mean he didn't intend it, as shown by the introduction.
All the videos I've seen of this piece play it straight, and one of them is labelled ABRSM so I'm guessing that it's the same on the CD that comes with the exam book.
Should I even mention it to my student? It would seem that swung is the composer's preference!