Hmmm... the node setup you are showing there is not at all what I meant. I was at work myself and did not have Poser available, and it's so difficult to convey node setups without a diagram!

As I see it, you have made two differences compared to the original shader:

1. The Velvet_Colour is now white (or near-white). It's this alone that has lightened up the feathered area on the back.
2. The displacement map now has something (I can't see what) done to it before being plugged into the displacement channel.

But you have not used the displacement map to control the shading of the feather area, which is what I thought might help most of all.

You've added the blend node at the bottom, but it is not plugged in anywhere, so it isn't doing anything.

I'll set up a shader to show what I meant - it will be much easier to understand than mere words.
It should work a bit better... or it might not... but I think it will!

Back before bedtime....

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)