I hope he recovers fully and quickly.
Make sure he gets a very good lawyer...this is when you want a very hungry shark on your side.
Good advice to not do anything to the bike except keep it somewhere safe. Perhaps have the shop just evaluate the condition of the frame, etc. Under most insurance that is a separate settlement than the physical/mental injuries.
When it happened to me I received full compensation to replace my bike within 30 days while the law suit took over 2 years to settle.