To me, they using their phones, even after being warned to not to use them, is just a plot hole to push forward the history. Is weird how Sorawo knew about Kisaragi Station but not what happen if you use your phone. IMO, it would feel more natural if Toriko tried to make the call on her own but...
I used to feel bad for Toriko at that part, but you know what? Maybe you could say this is a unintentionally payback(? Let me explain, at some point (vol 8 of LN) Toriko tells Sorawo how well aware she was about Sorawo falling in love with her, since they very first encounter, apparently Sorawo...
Because Sorawo thinks this is something like the revolting building in the Yamanoke encounter. And since they were to spend the night in the hotel they could as well explore a little and find a room in which they could sleep more comfortably.