I was finally able to speak to the fellow I bought him from. No way it can have favorelle.
He does have a lot of silkies.
A new pic for fun. Didn't know a silkie mix could have light feet. He's starting to get a few green feathers in his wings.
According to niclandia, a male silkie over a white or yellow shanked hen will give sex linked offspring, females with dark legs/skin, males with light. That must be your cross.