I read this and we cite it in our book. He gets everything wrong and makes wild claims. Then he admits he didn't really research his topic. He lists all the Russells he can think of that may have been Masons to infer that C. T. was one, then tells his readers he hasn't connected them. Bad book.
An example of his poor work is his claim that J. Paton baptized Russell. Russell was baptized in 1874, long before he met Paton. This is the only point we note in Separate Identity. Nothing else in his book is worth noting.
Springmeier has a troubled personal history. Personally I look deeply into a books quality when that's the case.