Personally, I think the twist should've been revealed either earlier (to quickly establish the real plot hook to garner reader's interest) or later (building up a decent readerbase first with the story focusing on Ko and his time in LEECH, before using the twist as an "end of part 1"). Putting the twist in chapter 5 while the readers are still trying to familiarize themselves with the characters and plot can be quite disorienting, and more importantly, alienating.
Could it have worked in any other magazine serialization? Possibly. But definitely not one as cutthroat as WSJ.