This can be thought more as a foreign country having another nation's military in their country. (Think America's many bases in far too many countries.) Is there anything else to say? I don't think so! If I missed anything, or if you have your own argument, let me know!
Looking at the physical, Nod-Krai is not a part of Snezhnaya. Nod-Krai has its own Statue, its own Oculus, its own sigil, and worships its own God. Snezhnaya also has its own Statue, its own Oculus, its own similar and worships its Archon. Whilst Nod-Krai plays host to the Fatui,