The reason for this is the following：
1. The coach has declared that he will not wear protective gear and participate in actual combat.
Secondly, there will be bumps in Taekwondo. Students should be psychologically prepared before signing up, plus it is an adult class.
It is inevitable to fight in actual combat, or he insists on it himself. I think if the Taekwondo Hall is in charge, it can be closed directly. You don't have to practice anymore.
However, if the coach of the temporary guest student cannot provide the credentials of the Dojo student, then he should be responsible.