I've been puzzling about that myself since I cropped this. It's possible; Donna had a lot of shit going on with the Darkstars and Titans and the divorce at this point, so you could make an argument for her not immediately returning to Themyscira when Circe finally let them go (there were a couple points where she was off-planet for probably a week or two at a time, if nothing else, which you could finesse the timeline to line up with Themyscira's return). And Artemis moved to Boston immediately after the Contest, so Donna would really have had no reason to run into her at that point, even if she did find time to visit home or Diana.
Does come across a bit weird, though, that Donna had no involvement in any of that whatsoever. Of course, so much of that storyline was pure fecal refuse to begin with, a nice vigorous retcon could probably only do it good.