Auto Insurance Claims: Retracting Statement to Ins. Adjuster, insurance fraud, serious auto

Question
My son (adult) received a concussion in a very serious auto accident in
which he received a DWI ticket and failing to merge properly ticket.  He was
in and out consciousness at the accident sight, was taken to an ER, and
discharged 8 hours later & took a cab home.  His license was not taken.  
Within 24 -48 hours of the accident he was reporting his accident to his
insurance company and denied that he was drinking (all recorded/oath,
etc.),  His head was not clear and he definitely had gaps of memory of what
went down at the accident.  He since has received car accident settlement
information and the Ins. Co. is proceeding with the bank re: lien.  He wants
to report to the insurance that he WAS drinking before cashing/signing any
documents because he doesn't want to be charged with any type of
insurance fraud/ or it not back him up on any other claims from the other
party.  Is it too late? Is the damage done already?  He's very frightened on so
many levels which he very well should be but his own insurance company
should be completely informed.  Right?

Answer
He should call the insurance adjuster now and explain what happened.  Explain he was suffering from a head injury and not thinking straight.  This should be considered a reasonable explanation for lying.  However, the longer he waits, the less credible an explanation this becomes.  They will find out later when they run his driving record.