I wonder if this article was written by a person who has done extensive business in Korea or deeply understands Korean culture.
Yes, mock funerals exist. They are done by fanatical Christian pastors in general as a business, because these pastors have a lot of control over the people who attend their services. It is almost like a niche sect thing.
Korean corporate business culture has been relaxed unimaginably even compared to two years ago.
This article contains a grain of truth, but mostly seeks sensationalism.