Yes, it was enough to save Noah.
Even Christ's closest disciples didn't understand the cross and Christ dying there...before He died there.
Why would one think that Noah had any knowledge of 'the preaching of the cross'?
Luk 18:31 Then he took unto him the twelve, and said unto them, Behold, we go up to Jerusalem, and all things that are written by the prophets concerning the Son of man shall be accomplished.
Luk 18:32 For he shall be delivered unto the Gentiles, and shall be mocked, and spitefully entreated, and spitted on:
Luk 18:33 And they shall scourge him, and put him to death: and the third day he shall rise again.
Luk 18:34 And they understood none of these things: and this saying was hid from them, neither knew they the things which were spoken.