Question on creating content.

Hello,

So I was playing a game created by Lloyd Krassner and really enjoyed it. It is called Imperium of Man. Sadly the creator has passed on and I have made some content for it. I was wondering if I may post it via Board Game Geek's files (since that is where I found the game) and who I might ask for permissions to do so?

I understand this may not be the place to ask, but I am not sure where to reach out.

Thank you.