From my understanding, the point of the matter is this: claiming the knowledge however erroneous is not coming from men but God himself. Remember, the small group of guys unequivocally state they are being "spirit directed". They are saying the mistakes are not mere imperfect human (gross) error, its the Holy Spirit. The HS told them falsely.
...... And that everyone is the unforgivable sin. Attributing wrong to the Holy Spirit.
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1 John 4:1 WEB
Beloved, don't believe every spirit, but test the spirits, whether they are of God, because many false prophets have gone out into the world.
1 John 5:5-6 WEB
Who is he who overcomes the world, but he who believes that Jesus is the Son of God? [6] This is he who came by water and blood, Jesus Christ; not with the water only, but with the water and the blood. It is the Spirit who testifies, because the Spirit is the truth.