Hmm, now that you mention it, I can kind of see it. Certainly a better fit than other recent attempts like, say, Booster Gold.
Yeah, it’s a part of this different universe in White Knight/Curse of the White Knight. In fact, I believe they do reference that episode of BTAS in those comics at one point. It’s definitely the most unorthodox of the Harley pairings I’ve seen, but I think for that universe it works.
Also, if you haven’t read those books, I highly recommend them. Of course, Curse isn’t on here yet, but White Knight is, and we even did a book club entry for it over at WOB.