That means absolutely nothing. If you look at his FB page, he has never posted much. I think he is more interested in making jewelry than being on the web. Call him and see. I certainly have heard nothing about him disappearing.
Thank you diamond seeker - I did call and was able to commission a project. Not sure why no-one responded to my email, perhaps too busy making jewelry as you suggested.
For as far as I have known, SK had an assistant (been a number of different ones) that takes care of emails, web and social media. Maybe he doesn't have an assistant anymore so he is busy making jewelry. I did write to him a few months back and he was doing just fine and still in business!