US Passport - Is VOA at Zhuhai Ferry Terminal?

Hi,
I have a friend that has a 14 month overstay stamp from a popular SEA country..he ran out of money and long story but he has a family member living in Hong Kong now and he has enough money to pay the fine, although he will be blacklisted and banned from returning for several years...his concern is how immigration at HK airport will respond..can he get turned away and refused entry?
He also wants to travel to China ML, and wants to know if he could get a few month Visa take ferry to Zhuhai...also.....he does have an old 1 yr multi entry Chinese visa, would he be able to get one in HK and not have to go home (or courier) to get Visa stamp?
Also if he flys into Hainan and gets the thirty day VOA, can he ask for the 90 day multi entry to the Mainland instead, and would a letter neccessary to do so?
THANKS SO MUCH.