I've planned to go to Chime Long Hotel in Guangzhou in December.

I don’t think it will be less crowded than normal days, after all there is no Chinese holiday during that time. And I’m afraid there is no direct shuttle service from the border to the hotel. Maybe you cam walk to the neighbouring Zhuhai Railway Station, where you can take a train to GZ South Railway Station. At the train station, there are free shuttle buses to your hotel directly.