Reposting Flair's charts inline for better viewing
Mum shows Silver with a yet unknown hidden
Dad shows Blonde Streaked and hides Flame or more recessive.
Kitten shows Cream
Cream is known to be recessive for Blonde Streaked and dominant to Flame, and must therefore be Mum's hidden whisker colour.
Mum shows Silver with Cream hidden as proved above.
Dad shows Silver with Dark Chocolate or more recessive hidden.
Kitten shows Dark Chocolate
Dark Dhocolate must come from Dad since it is recessive to Silver and we know that Mum hides Cream.
Cream must therefore be the kitten's hidden eye, and thus recessive to Dark Chocolate.
I believe this is sufficient proof as a second confirmation for the Saga project without birthing the kitten to pull it's hidden whisker colour.
My Dark Chocolate vs Cream test offspring turned out to hide Latte, so that project is ended.