The doe looks Russian Dove (Russian Blue + Mink), I have asked another established breeder who agrees. Which leaves a problem, you produced an obvious Mink (American Mink by the looks of it) in a litter to another Russian Blue. Impossible. Russian Blue x Russian Dove = All Russian Based. Is it possible she was paired with another male? Do you have pictures of the sire?

Blue Beige or Russian Beige is generally RED + Russian or American Blue. Their eyes are ruby with a very pale/creamy coat. Think about the regular Beiges, only add a slight Blue influence. Also, Champagne is PED and since PED is less common that RED in the US, I'm thinking these guys are likely RED, but it's impossible to tell. I'd have to see more of the lighter eyed babies to be sure. Champagne is Black based PED though and I'm pretty sure these guys are mostly Russian based.

Left to right - I see a Russian Blue (the Rex) and a possible Russian Buff/Beige (probably Russian based, likely a true Russian Beige) in the first row. Second row, Russian Dove, Russian Dove, American Mink, Russian Dove, Beige or Russian Beige (some sort of RED).