If you’re on facebook (or have a friend that is and is willing can ask) then it may be worth shooting him a message - or a post on there in the hope that one of his fans may be able to help you out?
https://www.facebook.com/mike.butkus.9
Good luck with it mate 😃
JEDIT - he may also be contactable at the following, too:-
https://www.deviantart.com/butkus
https://gumroad.com/mikebutkus
http://mastersofanatomy.com/mike-butkus