We don't know that he didn't try to call, or that he didn't knock on the door. The hotel may have declined to "check" on a guest at the behest of another guest. I wouldn't like it if someone I barely knew got the hotel management to check my room. It might be that Garcia thought Joran was ducking him and that if a casino manager called, Joran would contact him. I think Garcia intuited that something was wrong and tried to find out if Joran and Stephany were together. He might even have thought they were just ducking her family and wanted to give them a heads up that she was "missing." Or he might have known about Joran's past and got very nervous when he heard Stephany was missing and then tried to intervene without getting in too deep.
We don't know, yet. but I'll bet Garcia will be on GVS or NG or Geraldo or Dateline as soon as LE officially clears him. His story will be ,sot interesting. however, I think he is just part of the puzzle that led to Joran finally get getting caught, not a major player in the murder itself.
