Rumoured by whom? Not by anything stated in that article.
While I have tremendous disdain for the "distracted driving" defense, the situation presented in the article doesn't sound like that's the case. The driver not only crossed the opposing lane of traffic and struck someone, they continued off the shoulder (on the wrong side of the road) and hit a tree.
If alcohol truly wasn't a factor, this sounds like someone who either fell asleep at the wheel or has a medical condition (diabetes, epilepsy, etc.) which caused the loss of control.