Assuming your brushed steel cats aren't hiding anything else, that would be correct.
The boardwalk kitty has a 50% chance to pass boardwalk and 50% chance to pass its hider. The partner has 50% chance to pass brushed steel and 50% chance to pass its hider.
If the boardwalk grannies are solid, it would give you 50% boardwalk blue hiding brushed steel and 50% pure brushed steel cats.
Now if a granny was hiding faded flower, that's a whole new punnet square
