I haven't heard of the Baltimore Catechism teaching that people are saved by false religions. It states very clearly;
Q. 508. Why did Christ found the Church?
A. Christ founded the Church to teach, govern, sanctify, and save all men.
Q. 509. Are all bound to belong to the Church?
A. All are bound to belong to the Church, and he who knows the Church to be the true Church and remains out of it cannot be saved.
And also later on it says;
Q. 515. How do you answer such excuses?
A.
1.(1) To say that we should remain in a false religion because we were born in it is as untrue as to say we should not heal our bodily diseases because we were born with them.
2.(2) To say there are too many poor and ignorant in the Catholic Church is to declare that it is Christ's Church; for He always taught the poor and ignorant and instructed His Church to continue the work.
3.(3) To say that one religion is as good as another is to assert that Christ labored uselessly and taught falsely; for He came to abolish the old religion and found the new in which alone we can be saved as He Himself declared.
Q. 516. Why can there be only one true religion?
A. There can be only one true religion, because a thing cannot be false and true at the same time, and, therefore, all religions that contradict the teaching of the true Church must teach falsehood. If all religions in which men seek to serve God are equally good and true, why did Christ disturb the Jєωιѕн religion and the Apostles condemn heretics?
https://www.catholicnewsagency.com/resources/catechism/baltimore-catechism/lesson-11-on-the-church
The following excerpt from the Baltimore Catechism is the creeping heresy, among others, that was subtly infused into this Americanist "catechism". The slithery that is you conveniently omitted it:
Q. 510. Is it ever possible for one to be saved who does not know the Catholic Church to be the true
Church?
A. It is possible for one to be saved who does not know the Catholic Church to be the true Church, provided that
person:
1.(1) Has been validly baptized;
2.(2) Firmly believes the religion he professes and practices to be the true religion, and
3.(3) Dies without the guilt of mortal sin on his soul.
# 2 states that if the person believes and practices his false religion of Judaism, Islam, Buddhism, New Age, etc. to be the "true religion", he can be saved. This is absolutely against numerous ex cathedra decrees by various popes, which affirm that no person outside of the Catholic Church can be saved. Such persons, as specified by these same infallible decrees, are Jєωs, heretics, Muslims, schismatics, pagans, non-believers, etc, who are damned eternally.
Also with respect to where he said that Hell, it it exists is almost empty, I repeat what St Alphonsus de Ligouri said, "Those who deny the existence of Hell are those most likely to go there."
You're insidious. St. Ligouri didn't say Hell is almost empty. You said it.
St. Ligouri is communicating the fact that people, who don't believe in Hell, usually commit the most heinous crimes because they think there will be no consequences for their sins, thus, these very sins warrant them eternal perdition more than anyone. That doesn't mean people who commit lesser evils, but still die in the state of mortal sin, don't go to hell.