If the framework is corrupt everything inside is compromised.
Whether the WBTS is right or wrong doctrinally is besides the point.
Their hidden message and framework that we are put right with God by means of finding and following the "correct" doctrines is an apostate teaching called "ethnocentrism".
Their hidden message and framework that we are put right with God by means of rule-making and rule-keeping is an apostate teaching called "legalism".
The same with moralism and Gnosticism.
According to the "good news" in scripture we are put right with God by means of IMPUTED righteousness granted as a "free gift" through unmerited favour. The criminal who died next to Jesus did not earn his way into paradise/heaven - and neither can we.
(Their own publications debunk "legalism" as a denial of Christian faith - apostasy.)