You'll find the password for the red cards after you get into Bridget's room --
-- and break into the safe there.
How do I find and open the safe?
What do I do with the code page?
Solving the code page in the safe gives you the password. Enter it into the red cards as you did with the green ones. This tells you --
-- what you need to do with the deck of cards you found in Zoe's safe and what their significance is.
What do I do with the deck of cards?