No, I'm 100% sure there are no other birds as I had them separated from my other birds and they were in a different location quite far away from our other chickens. We have a large farm. They were acres apart from other chickens with trees and hills and rivers between.
Yes, they are silver grey dorkings.
Below is more of what I was expecting. The chick on the bottom right is the male, but still looks different to mine I think.
I just hatched 2 Dorking chicks yesterday and they don't look anything like typical dorkings. I hatched chicks from the same hens last year and they had the traditional chipmunk pattering. This year I had the same hens in a pen with 2 roosters, one was a new one from a different line and the...