It may - but my hunch is that the methodology was already in place by the time those trips occurred. Note that Kiichi Hogen (from the 1100's) was familiar with that cosmology - so there's no need to go back to pre-war China as a source for the information.
I am unfamiliar with the hachiriki outside of an Omoto/aikido context. I'd be especially interested in any examples from the shrines Takeda is said to have trained at. I agree that Omoto would have had their system well-established by the time Deguchi went to prewar China, but I am curious to know if some of the Shinto concepts were not so commonplace in Japan but well-established in the choice for a Utopian colony. Also, where would Osensei have first encountered hachiriki?
Thanks for your research and comments so far