Species is an artificial construct try classify life forms. Since life constantly evolves, there are many instances where different forms are still related enough that they can produce viable offspring. Carried an extreme, we could say that carrots and hummingbirds are related (and, in fact, some genes are shared by plants and animals). keep the classification system useful, while acknowledging that life forms are a continuity, we have make choices. In addition species, some schemes use subspecies, or even “races.” Over time, we expect these groups continue evolve until they are truly different species. The criteria are not limited fertility; physical and behavioral separation are also elements. A group that has existed physically separate from its ancestors for hundreds of generations is legitimately a separate species. I doubt very much that “human politics” is an important factor in taxonomy.

Lots of organisms considered different species can nevertheless interbreed. Horses, donkeys, and zebras, for instance. The problem of what is and is not a species is more difficult than it might as first seem, and there are lots of borderline cases. [evolution.berkeley.edu] [en.wikipedia.org]

much in the same way homosapiens were able to interbreed with homoneanderthalis, they may indeed be a separate species but of the same genus, and therefore would still be able to procreate outside of their own individual species.

I think they are the same genus, not species. Lions can breed with tigers, they are different species, but belong to the same genus