When I dropped off my AH to rehab the wife of the couple that runs the program told me to "enjoy the peace" while he was gone. She was so right!
Your dad just may need some space while he gets treatment. Even more so if he wasn't willing to go on his own.
I know that my husband often felt overwhelmed with people calling and asking how he was doing. (they also drove me a bit crazy too b/c if they didn't talk to him they then called me to see what I knew.)
Also rehab can be complicated in getting information. Unless your dad has given permission to the staff to give you information they will not do so. Even if there is a release they may be very vague in what they share. Information shared in therapy is very private. When ever I would ask staff how my husband was doing in rehab the conversation would quickly turn to what am I doing for myself and the kids. I now understand why- his recovery is his job and my recovery is my own.