Can we use a 72 hour visa? Please help us!

Hi I have to organise a visit to Hong Long for one of our Businessmen - he is currently on business in South Korea and needs to come over to Hong Kong to visit three of our Suppliers in Hong Kong. He will then return to Incheon Airport in Korea and has his return ticket to the UK booked for Sat 21st Feb. What type would we need to get for him to be able to land into Hong Kong International Airport and then travel to Kwun Tong in Shajing in Shenzhen. Look forward to hearing from you.
Thank you