If you have already helped Lin with interrogation and read those two letters (That pema gave) from pathik, lin will come to airtemple island at evening, and then next day, you can start quest 15
Well, whatever happened, the restarted playthrough worked
If you find what happened, let me know. I will update it in walkthrough :)
how i can continue the cheating route of pema ? I already help her for chest pain but i can't make more.