A Jehovah's Witness may dispute the quote and the Watchtower Society provided more information in German, but in English, the entire quote appears like this:
“Our coming to know "the truth" - the entire body of
Christian teachings that has become part of the
Bible - and adhering to it are essential for our
salvation”.
They put quotes around "the truth" as all Jehovah's Witnesses know (consciously or subconsciously) refers to the organization, its interpretations and especially its primary indoctrination and "new light" tool the Watchtower.
If the intent, when originally presenting the phrase -the truth- was just to refer to the information in the Bible, the sentence at best could have been phrased better, at the very least there should not be quotes around "the truth". By doing that, the writer(s) knew exactly what they were doing, implying, and how that statement should be taken. "The truth" - in quotes like that, again refers to the organization and its teachings.
If any Jehovah's Witness is denying that phrasing, intent, and reference to "the truth" they're just being disingenuous and/or experiencing cognitive dissonance.
When you leave the Watchtower organization, its teachings, and/or interpretations, Jehovah's Witnesses say you have left "the truth".