It says they had knowledge of the word. that could save them
it does not say they were saved by those words.
again read.
But it has happened to them according to the true proverb: “A dog returns to his own vomit,” and, “a sow, having washed, to her wallowing in the mire.”
2 peter 2: 12 But these, like natural brute beasts made to be caught and destroyed, speak evil of the things they do not understand, and will utterly perish in their own corruption, 13 and will receive the wages of unrighteousness, as those who count it pleasure to carouse in the daytime. They are spots and blemishes, carousing in their own deceptions while they feast with you, 14 having eyes full of adultery and that cannot cease from sin, enticing unstable souls. They have a heart trained in covetous practices, and are accursed children. 15 They have forsaken the right way and gone astray, following the way of Balaam the son of Beor, who loved the wages of unrighteousness; 16 but he was rebuked for his iniquity: a dumb donkey speaking with a man’s voice restrained the madness of the prophet.
17 These are wells without water, clouds carried by a tempest, for whom is reserved the blackness of darkness forever.
Jude: 4 For certain men have crept in unnoticed, who long ago were marked out for this condemnation, ungodly men, who turn the grace of our God into lewdness and deny the only Lord God and our Lord Jesus Christ.
5 But I want to remind you, though you once knew this, that the Lord, having saved the people out of the land of Egypt, afterward destroyed those who did not believe. 6 And the angels who did not keep their proper domain, but left their own abode, He has reserved in everlasting chains under darkness for the judgment of the great day; 7 as Sodom and Gomorrah, and the cities around them in a similar manner to these, having given themselves over to sexual immorality and gone after strange flesh, are set forth as an example, suffering the vengeance of eternal fire.
8 Likewise also these dreamers defile the flesh, reject authority, and speak evil of [dignitaries. 9 Yet Michael the archangel, in [contending with the devil, when he disputed about the body of Moses, dared not bring against him a reviling accusation, but said, “The Lord rebuke you!” 10 But these speak evil of whatever they do not know; and whatever they know naturally, like brute beasts, in these things they corrupt themselves. 11 Woe to them! For they have gone in the way of Cain, have run greedily in the error of Balaam for profit, and perished in the rebellion of Korah.
These are the same people. Both peter and Jude say their condemnation was fortold and always in view., these were not saved people who were deceived. These people knew what they were doing. So it will be worse for them then the rest. If would be better if they had not KNOWN the way..