Kay was prepared to not listen to Chas and just leave, but the moment John told her to stop, she did infact do as she was told. She didn't know if it was because John asked or the bond making her stop, but she just did. "She said she could hear someone but she couldn't focus on them to know how to help. She needed the map to hone in on them" Chas explained to John, which just made Kay think all the more that it could be her sister in danger. 

Josh smiled softly at Serena, "Well it means a lot that you and your friends put yourselves in harms way for us...for her" he told her, gesturing at Trish. "I just wish we could help you guys more" he told her honestly.