Hi Minimus,
In regard to your question, I believe it was Rutherford and his associates who went to prison, though they were originally followers of Pastor Russell.
Of the Watch Tower Eight who were sentenced to Federal prison in 1918, one resigned from the Watch Tower editorial board in 1922. This was Fredrik H. Robison. Robison attended Franklin College, Butler College, the Winona technical Institute, and the John Herrin Art Institute. His linguistic talents included Spanish, French, German, Japanese, as well as New Testament Greek. About a year after he came in contact with Russell's works he was invited to Watch Tower headquarters, then located in Allegheny, Pennsylvania. He then became Russell's private secretary. When Russell transferred his operations to New York State in 1909, Robison was made secretary in charge of foreign work. After Russell's death Robison stayed with the Watch Tower, serving on the magazine's editorial board. After his release from prison in 1919 Robison resumed his work on the Watch Tower editorial board.
However, after coming in contact with the Concordant Publishing Concern and their Bible translation the Concordant Version, Robison found that he had more in common with their belief system than with the Watch Tower under Rutherford. Therefore, his position in Rutherford's organization became precarious and he resigned in 1922. Had he chosen to do so Robison could have been a formidable opponent, possibly forcing Rutherford to make concessions. Instead of fighting inside the Watch Tower, Robison stood up for his beliefs by assisting the Concordant group.
So according to the Watch Tower's definition of "Faithful to the End," Fredrik H. Robison would have missed the boat that carried Rutherford and his cronies to their reward.