It might be possible to contact Jeff Tunnel. He does have a Facebook page on which he occasionally posts.
http://www.facebook.com/jefftunnell
If he doesn’t, he may know someone who does. There has been mention of supporting the Dynamix adventures in ScummVM, but I don’t think that anyone has picked it up. Still, it may be worth mentioning it there if any RE work on Johnny could be applied to the Dynamix adventures. If you could generate any interest in some of the devs there, who knows?