Why does Nick decide to go to Winston-Salem in Chapter 25?

At the beginning of Chapter 25, Nick storms into BR's office, where BR is meeting with Jeannette. BR tells him that he should take a leave of absence, but Nick dismisses it, saying that he has too much to do. He wants to talk to the Captain, who by now is in the hospital. Returning to his office, Nick finds FBI agents upturning the contents in a search. he decides to break his bond and go to Winston-Salem to see if the Captain can help him.