As Catholics, when we speak of a teaching being “orthodox,” we mean that it conforms to authentic Catholic doctrines. When we speak of a catholic being “orthodox” we usually mean that he or she is concerned that Catholic doctrines are being taught as they are intended by the magisterium.
Unfortunately, there are some who do not teach “orthodox” doctrines, either out of ignorance or deliberately. Those who unintentionally teach falsely may not know that they are not being 'orthodox" in a particular area of faith, and on a number of points we may all be guilty of unknowingly teaching the faith incorrectly. The important thing is to be willing to submit to the teachings of the Church when we find we are in error.
Those who intentionally mislead, misquote, and in other ways teach unorthodox doctrine are the ones causing division. But I agree with you that in Christian charity, we should assume that everyone wants to be “orthodox” in their treatment of the faith unless and until they show an unwillingness to submit to the teaching authority of the Church, after being shown their error from an authentic source.