I think I broke the "investigate the mayor" mission by sequence breaking?
So I made myself a "brute force" key and got in to Longson's apartment way early, and found out about and triggered the conversation with his "wife."
Now I've been giving a mission to find dirt on Longson, but going back and trying to talk to the wife again doesn't seem to do anything.
Is there a specific action that completes the mission, or am I gonna have to restart the game?
Yes, talking to the "wife" early breaks the mission and you have to restart.