Since Hollywood moves because of money, it might be because somebody lost a good deal of money over his death. Maybe he agreed to a major part in a movie.
Most likely an insurance company is investigating. They are not in the business to pay out money if they do not have to.
However, I do not think Matthew Perry was getting any roles last year. I also do not think ANY insurance company would cover him based on his drug abuse.
there is a blind gossip item that this is really about a 4 part documentary that is being filmed