Having a knowledge that Catholicism exists does not equate to belief in our doctrines or teachings Remember, these folks listen to their ministers teach that there is much wrong with Catholic beliefs, such as the primacy of the Pope, Marian doctrines, faith, etc. No wonder they have difficulty making the leap into our Church, after constant exposure to being taught how wrong we are.
You need to rethink this, that simply having exposure to Catholic teachings does not guarantee that God will give them the gift of faith to believe them. So they can still be ignorant, and God alone sees the heart.
Luke 12:48 “But he that knew not, and did commit things worthy of stripes, shall be beaten with few stripes.”