Can "only" be used for emphasizing that-clause?

A. We had been told only that something was wrong with her liver.

It looks like "only" is used for emphasizing "that something was wrong with her liver".

Q1) Like in A, can "only" be used for emphasizing "that-clause" in a sentence?

Q2) Is sentence A correct?

Q3) Without the word "only", is the meaning of sentence A changed?