Russell's views have a very long history, back to the Second Century CE at least. Adopting an idea does not mean you've stolen it. Do you believe the world is round? From whom did you steal that idea?
Mom's books, including forthcoming volume 2 of Separate Identity, trace the history of Russell's doctrines. That a doctrinal set has a history does not mean believing it is intellectual theft. If we adopt that viewpoint, then everything we personally believe we 'stolen' from someone.
In the 1790s Joseph Priestly wrote a multi volume history of non-Trinitarian belief, taking it back to the start of the second century. [99-200 CE]. Non-Trintarian belief was common in the United States among Congregationalists in New England. Some of them were Arian, some were Sebellian, some were Socinian, and some were Subordinists (Russell's belief system). But they were all non-Trinitarian.
L.E. Froom wrote an abbreviated history of conditional immortality doctrine called The Conditionalist Faith of Our Fathers. It describes the history of those who rejected eternal torment doctrine. Russell came to it through Jonas Wendell, George Storrs and G. Stetson. There was in the 19th Century a proliferation of books denying Hell Fire doctrine. Many of these were written by prominent clergy.