And Catholics disagree amongst themselves.
Your point is?
If that invalidates Scripture as the final rule of authority, then the whole Catholic church is invalidated by the disagreeing believes of Catholics.
No, sorry. The Catholic church has one teaching. It is in a book called the Catechism (which happens to be Greek for teachings).
Insofar as any individual Catholic disagrees they are incorrect.
If you cant see how this is entirely different from the Protestan Sola Scriptura individually led to truth by the Spirit chaos, then i am sorry.