Even if he did nothing wrong.
Lawyering up is an intelligent reaction especially if he did nothing wrong.
I can assure you that if I were in his position and knew I had done nothing wrong, calling my lawyer would not have been job 1.
Memory loss can be real. I was in an accident 30 years ago. Car swerved off the crown of a rain slick road toward a ditch. No memory of sliding into the ditch, the driver trying to gun it out of the ditch, hitting a culvert, being thrown against the ceiling. Woke up realizing I had been in an accident. Had 11 broken ribs and a punctured lung. Three ribs were overlapping and could not be set. The rest were cracked or broken in position. Healed fine. Won a Limbo contest 2 1/2 months later. Oldest contestant. When there is a sudden severe pain, I think that sometimes the brain cannot store the memory. I still have no memory of the missing pieces 30 years leter. I think it is called retrograde amnesia.