Maybe that is just one group [tribulation saints and the followers of antichrist]
>The great number who have come through the tribulation, who have washed their robes in the blood of the Lamb, who are pictured standing before the Lamb in the midst of the throne, clothed in white robes, with palms in their hands worshipping him, Rev. 7:9-17, are the followers of antichrist?
Strange twist you have there. Please explain.