You're probably not gonna learn more until they or someone close to them actually say something about what went on from their side. The WWE side they put out with their statement was bullshit according to all the trusted reporters. All we know is they're invested in being a tag team and want the tag titles to be featured more. WWE had no plans for them as a team or the titles and after some back and forth, they just walked. There's indications there's more to it but no one is saying anything yet. And other talent according to people like Meltzer, SRS, etc indicate they're fairly supportive of Sasha/Naomi's issues but don't like that they walked out mid-show (some even indicated they didn't mind them walking out, just don't do it with so little time left and people have to scramble).