Whether or not Anan is right and he can be ex-communicated by talking about what someone talks about in a confessional, McBride asked him about his opinion of whether or not Ryan was suicidal, not what he talked about during confession.
Although at 33:28, the traffic is seen going backwards, it is simply a visual device to suggest setbacks in the plot.
Season 1, Ep 5, at 22:37, when video pans to watch traffic, the traffic is moving backwards in reverse.
As Lucy is swimming laps (in the 46th minute of the episode), the wake of the camera person (following beside her) can be seen several times in the foreground of the shot.
Father Anan tells Billy there are 5 acts which can excommunicate a priest. According to Catholic law, there are actually 13 acts, 10 of which are applicable to priests.