According to the writer of 2 Kings, this verse shows how God helped the woman by letting her meet the king at the right time. She was able to get back her house and land because the king listened to her story and believed in the miracles Elisha did.
2 Kings 8:5: And it came to pass, as he was telling the king how he had restored a dead body to life, that, behold, the woman, whose son he had restored to life, cried to the king for her house and for her land. And Gehazi said, My lord, O king, this [is] the woman, and this [is] her son, whom Elisha restored to life.
Proverbs 12:19 states that truthful lips endure forever, while 2 Kings 8:5 highlights the specific fulfillment of Elisha's prophecy, which may imply divine intervention rather than human truthfulness.
Proverbs 12:19: The lip of truth shall be established for ever: but a lying tongue [is] but for a moment.