Well Kiawe is a special case since he had a Z ring and Z crystal since the beginning of the series, and it was passed from his grandfather. In the others case, it's going to be harder to specially find Z rings separately, although not impossible. Either way, I do think that Mallow, Lana and Sophocles might receive Z rings in the future, but I don't think it'll be in this episode for Lana.
Anyway, it's really interesting that TR are again not in the episode. Either they really might be getting phased out gradually from the show (which is almost impossible), or they'll appear in episode 33,which is again doubtful since they don't have a reason to be in Akala. Well since they can't be away for so long, this might mean that Ash and everyone may return to Melemele again after episode 33 just so TR can appear again, before going back to Akala.