Think about this.
Men wrote it. Men compiled it. Men canonized it. It was human hands which put this book together. Yes, the Holy Spirit inspired them but humans were the proximal means by which this book was assembled. Did the Holy Spirit take a permanent vacation when the job was done? Does he no longer work through the Church and guide it?
Moreover, there was a time in Church history when there was no New Testament. Read Acts 15. When Paul and Barnabas got into a dispute about circumcision in Antioch, they could not say "let's see what the Bible says about this". The New Testament had not been assembled. Instead, Scripture tells us that they returned to Jerusalem to consult with the "Apostles and ancients".
That's how it was in the early Church. It was men who guided it, not a book.
You’re confusing the work of the Holy Spirit to lead and guide, with doctrine which explicitly and exclusively comes from Scripture (2 Timothy 3:16).
In this case, the Catholic Church is espousing doctrine not in Scripture, something Jesus specifically condemned (”teaching for doctrines the commandments of men” Mark 7:7).