Would this be a case of negligence in the nursing home?

My father lives in a nursing home. his roommate is an Autistic gentleman who is in there for Kidney & Bladder problems. He has no problem with dementia or confusion. He has a remarkable memory probably due to his autism. He told me of an experience he had in the dining room a few days ago at lunch. There was a lady sitting directly in front of him at another table. She was facing him. During lunch time he noticed that the lady had her eyes closed and hadn't touched her food and was slowly turning blue. He notified a dining room aide who just touched the lady on the shoulder and said " Ms. Jones you're not eating today" and just walked away. She never bent down to look in her face. The woman was sweating profusely as she was turning blue. As lunch progressed he alerted the staff about the ladys condition 4 times and nothing was done. they never walked over to her again until he went over and told them her face was in her food. He said 4 aides came over to check on the lady. At that time he told them they had better call 911 or she was going to die. It was to late she was already dead. This man does talk alot and I notice that they tend to ignore him or just say oh yeah and walk away. Due to his remarkable memory he knows the times he alerted them and the names of the people involved. He told me today that he mentioned her name to the charge nurse and she quietly told him that "we don't talk about that". I do know that the lady he named did die a few days ago. I also know that residents can come up with all kind of story's. But this man is factual to a fault. He is very clear headed. They have also moved up his discharge date and when he rings his bell they come immediately. (Thats almost unheard of in a nursing home) I wonder if I should say something to the family, the police, maybe the Company Headquarters.. I don't know. If it were my dad I'd want to know if his death could have been prevented by getting help at the first sign of distress.