How could his professional associates have been unaware of what was going on, when rumours of it even reached me up in Scotland?

They probably weren't "unaware." It's possible many of them knew. But the horrible risks of speaking up -- or speaking out -- especially when there is money involved ... or the facts contradict as you said in your post, a beloved public figure -- are real and potentially devastating. The same holds true if the offender has power -- status -- position -- wealth.

This is a shameful thing about society -- and maybe human nature itself. That, along with the "blame the victim" rationalizations, being a whistle-blower can literally put your life and the lives of your loved ones at risk. It's no wonder people keep quiet under those circumstances. The courage it takes to speak up isn't applauded. Instead, the costs are often swift and devastating.

As a psychologist I have found this fact of human nature fascinating and deeply disturbing -- in equal measure. It says some terrible things about us as a species. I can't say I like it a bit.

In fact, I find it brave of you to write this post. Good work!!