Is he still high?
Seems to me that a coverup is unnecessary if all he was doing is speeding. You don’t bring this many bad news cycles down on yourself to hide the fact that you were driving a little too fast. He’s hiding something more significant.
So what is it? He jumped on that breathalyzer test, but never took a urinalysis. I think some substance other than alcohol was involved. He crashed his car while inspecting storm damage before dawn. So either he was hallucinating or telling a really stupid lie, either of which would support a drug use theory.