Ask HN: Is anyone familiar with the Asimov estate?

I run a small press focused on science fiction, and I'd like to start publishing some popular science texts as well. I really loved reading "The World of Carbon" by Isaac Asimov when I was younger -- it's a fantastic book on organic chemistry. It's been out of print for many decades, but it will be a while until it's in the public domain (published around 1960). I'd like to reprint the book with annotations, but the firm managing the literary portion of the Asimov estate (William Morris Endeavor) won't even acknowledge my queries about publishing rights. Does anyone here have any advice for me? If you don't have advice but are interested in this project I'd appreciate it if you could increase visibility of this post. Thanks!