That is entirely false.
In order to be saved, as a Catholic, you need 3 things : faith, sacraments OR desire for them, and good works.
Not any of the three can be lacking, unless someone suffers from invincible ignorance.
As for being saved only by one's own merits, that is logically impossible. All of a human's virtues come from God, whether they are aware of it or not. Goodness itself comes from God.
Where do you come up with these three things?
How can one have the faith "or the desire for them" when they've "never even heard of the existence of the sacrament of baptism?" Nobody desires that which they do not know exists. What you say is contrary to the catechism....
