There are verses right above those which state something more. You quoted parts of Mas. Rosh HaShana 17a which is talking just about the minim and the informers and the scoffers. I believe what I said still stands.
The rebellious Jews who have sinned with their bodies and also the rebellious people of the nations of the world who have sinned with their bodies descend to Gehenna and are judged there for twelve months. After twelve months, their bodies are consumed, their souls are burned, and a wind scatters them under the soles of the feet of the righteous, as it is stated: “And you shall tread down the wicked; for they shall be ashes under the soles of your feet” (Malachi 3:21).
But the heretics; and the informers; and the apostates [ apikorsim ]; and those who denied the Torah; and those who denied the resurrection of the dead; and those who separated from the ways of the Jewish community and refused to share the suffering; and those who cast their fear over the land of the living; and those who sinned and caused the masses to sin, for example, Jeroboam, son of Nebat, and his company; all of these people descend to Gehenna and are judged there for generations and generations, as it is stated: “And they shall go forth, and look upon the carcasses of the men that have rebelled against Me; for their worm shall not die; neither shall their fire be quenched; and they shall be an abhorrence to all flesh” (Isaiah 66:24).
Thank you for the information, I will actually follow up with him.