Board Thread:Lore Discussion/@comment-26145872-20160101184444/@comment-26896471-20160104103912

Assuming you mean thre Third Dominion, geography and tradition. The Aldmeri Dominion under Ayrenn incoroporated the Khajiit. In practical terms, dislodging Elsweyr from the Empire further weakens it and further shifts the balance of power.

In regards to your theory, there is no need as such for a third group, but the pull of the Khajiit (due to the reasons mentioned above) is far greater. But yes, Khajiit are a far more plausible addition than the Redguards, the next closest geographically.