Seems that Rutherford wanted to distance himself from Russell's interpretation and teachings.
Not at first; just the opposite. Rutherford's boiler plate stated Pastor Russell edited the Watchtower from heaven, or some such nonsense.
Russell was given the imputed "authorship" of THE FINISHED MYSTERY although it was cobbled together by others with dangerous fluff added.
I think when the Judge saw the magnitude of loyalty Russell had and how insurmountable it would be--he switched to his own devices and ideas.
Rutherford used any source available for any purpose suiting him. He was that particular.
Freddy obtained his foothold in the WTS chiefly by coming up with scriptural (ha!) justifications and support for the crazy ideas the Judge dreamed up.
Romans 13.1 was outstanding apostacy (Rutherford changed the meaning backward) on his part! Yet, Freddy managed to justify it until
1962. Then, it flipped back without any explanation whatsoever!