They had a plan that went very wrong, setting off a chain reaction that was aggravated by Crawford and Altherr's struggles (be they performance or health). I don't know if it was an analytics error or an old-fashioned scouting error, probably both, but they thought Hoskins would be more competent, and more importantly, offset by an elite defensive CF (as well as a very good RF) and a superior defensive 1B. Then Hoskins wasn't competent, the CF wasn't elite, the RF (either of them) wasn't good and Santana wasn't an upgrade.
Kingery was probably the least of their problems but I still believe he is talented enough to play multiple positions (plus why would the shifts bother him, he's a 2B anyway). He just needs to hit to have value doing it. Then Cabrera comes in and he doesn't hit either.
2019 is still going to have some holes, clearly. Either someone (Hoskins or Santana) will continue to play out of position and/or the SS and 2B will be a virtual rookie (unless they get Machado). The big question is Herrera.