Sounds like irrational behavior. Drug Induced or mental health issues? We'll probably get an accurate accounting sooner or later.
Something tells me those guys aren't quite telling the whole truth either. With the other half of the conversation dead who will argue?
Vol You may be right, that the students aren't giving the complete story. They did however call 911 during the incident and this from the link tells of a woman who also called 911 saying the same thing. that he tried to run them off as well from link "This comes after a woman's frantic 911 call indicates that Bironas, 36, tried to run her and her husband off the road" Very sad but frightening for the people he tried to run off the road.
The fact that his car smelled so bad I wonder if he went for a drive and fumes started going into his car which caused him to act erratic. I'd guess his SUV was fairly new so for it's exhaust to smell bad enough for someone to say something seems unusual.
This sounds to me like Ambien. He told his wife he was going to bed and then all of a sudden he winds up in his car acting unlike himself. I would put money on Ambien. Sad story.