If you made a mistake, then the correct decision would have been to distrust the pastor from the start. That is not good for any organisation, let alone a church. That would risk alienation of a perfectly good pastor, hurt feelings and a dysfunctional church. Whatever you could have done could result in damage. Starting off by distrusting the pastor would actively damage relations and is a bleak existence anyway. You made the best choice from a paranoid point of view.