Translation:The waiter is very busy.
"Server" should be accepted, especially since it's the gender neutral term. A waiter is a male, a waitress is a female, but a server can be male or female.
Very true! Well, word 종업원 literally means "employee" in English.
It seems for waiter and waitress in a restaurant, 서버 is used in Korean also:
서버 = 서빙하는 분 = 서빙하는 사람 = 종업원