Dad was attacked by another patient in the hospital. What should I do?

Dad left my home after having a Major Meltdown 10 days ago. He was admitted to the hospital on a 24 hr hold (due to confusion) and then moved to a procedure and treatment floor while having test done. While in there a young man who was also on his floor decided to smoke some kind of drugs in his bathroom & freaked out. The nurse had just transferred dad into a chair so he could be out of bed for a while & as she was walking out the door this man came into the room. She knew dad had not had any visitors except me and wondered what he was doing there. She turned around to look and he was punching dad in the face and head and had thrown him on the floor. Dad has had 3 strokes and has no use of his right side. he could not defend himself. (Even though at home with me he can be the devil himself!!) The nurse was also attacked as she went after this man and several staff members were hurt also. Security managed to subdue him and I was told he went to jail. When dad left my home he was very angry at me and still is. When I got to the hospital after they called me he started screaming for them to get me out of there and not tell me anything. I never got to see him for myself but my brother went up 3 days later and said dad looked very bad and his face and ears were swollen and black/blue. I asked him to take a picture with his cell phone but he forgot. He is RARELY involved in dads life so I don't expect much from him... The nursing staff told me they have no idea why this man acted out like this. HOWEVER.. In the hospital parking lot they have trolley service where they drop you off at the main entrance. The young lady who was driving the trolley asked me if I was here to see a patient. when I told her my dad had been attacked earlier that day she said "He's your dad? We all heard about that. Apparently the guy was in his bathroom smoking crack and flipped out & ran straight into your dads room" ...Oh Really?? The nursing staff "forgot" to mention that on the phone and never said a word about it when I came up to see what had happened. They were supposed to release dad to the nursing home but they keep saying that he will go tomorrow because he has this test and that test to have done. I am going to the nursing home this morning to fill out his admitting paperwork and will be stopping by the police dept to get a copy of the police report on this incidence. I would like to have an attorney look into this but I have no way of asking dad if that is something he would be interested in. Before he had his stroke he would have called an attorney himself. I am his POA so I can do it. Its just that I haven't seen him to be able to report to the lawyer about how bad his injuries are. I think its suspicious that they are doing ultrasounds on him when he had no medical reason to need one before this attack. He was all set to be discharged and now its been 5 days and they're still running test. Anybody have any suggestions?