Q.I Have Been Told I Have Honey Fungus In Our Privet Hedge. I Have Spoken To Next Door Neighbours About Taking The Hedge Out To Try
to destroy the fungus but they don’t want the hedge removed. What can I do as it is a shared boundary? Hedge is about 9’ high by 20’ long and about 6’ is dead or dying. A professional garden company has diagnosed the problem.

Certified GKH Gardening Expert
I wish I had better news but, unfortunately, you may not have a choice but to remove the hedge. Here's some info about honey fungus:
https://www.gardeningknowhow.com/ornamental/fungus-lichen/honey-fungus-information.htm