Question: Why is there a scene where the fake detectives are trying to listen to Roy's conversation with his doc? They weren't really cops, the fake hospital room didn't need microphones, etc.
Question: I didn't quite understand the ending. Was Angela fooling Roy the whole time, or did she decide to after she met him? Were Frank and Angela working together?
Answer: Angela was working with Frank the whole time, she wasn't actually his daughter. Roy's shrink (Dr. Klein) & Chuck Frechette (the money laundering guy) were in on the con as well.
If Chuck was also in on the con then why was Frank so beaten up? And why would they bring up the whole talk about the ashtray from the gift store and how the camera in there had seen Angela if Chuck was already supposed to know about it all?
Their whole plan was to get his vault password, how to get it? By making everything looks real. The death of Chuck -> Roy says he is the one who killed him -> His "daughter" is running because she is the main suspect -> Roy gives his password to the shrink so he can give it to his "daughter" That means Chuck, Frank, Angela, The fake police men, and the shrink are working together.
Answer: They needed to get the password for Roy's safety deposit box. They planted the camera and microphones so that they could listen in on the conversation and know what the password is.
Casual Person
But he gave the code to the doctor who was in on it.