Thanks for the clarification. The point is very simple - PRC students who make up a minority in his class visited him. The term is Guanxi.
The teacher in any school in Singapore assigned to liaise with parents will tell you that PRC parents will contact you, try to form relationship, ask you to visit their place of business, go for coffee etc. Also first to ask your mobile number.
Remember it was a PRC lady who falsified her educational qualifications that forced Yong Pun How to rescind his very own guideline on sending people to prison for this and she had testimonials from the well connected.