Please see my post # 32 for a discussion of the distinction between private and public revelation. I think it may be helpful for you.
You state:
The Church teaches that the entire deposit of faith was given at Pentecost, and our understanding thereof is what grows over time.
It is rather clear that the canon is closed for the CC and evangelicals, however, there are statements from both groups indicating that they receive "divine guidance" for interpreting the canon. After all, where else can you receive "divine guidance" except from the divine, and where else can you receive understanding of the things of God, but from God.