I have no idea, but I doubt the Greater Korean Republic had any interest in these Islands, so In my Opinion, I beleive the Islands are never going to be Invaded, for their is no use for them for the KPA War Machine, as thier main target, out off all Nations on the globe is nothing more but North America.

These islands are speculated to contain oil and natural gas reserves.  Aside from that, it is also a rich fishing ground.  The GKR may or may not have interest in these, but since they have either conquered, absorbed, or persuaded Southeast Asian nations to join the Republic, its probable that they may have some control over these islands.  Probably, its another supply of oil for them in addition to the oil given by Iran, Brunei, and Venezeula.  If they do control these islands occupied by the countries that joined them, then already have a bigger territoreal dispute with China and Taiwan, as with our world that South Korea and Japan have island disputes with China.

If the GKR could get them, they would. Why not? There would be hardly any resistance and they control most of the countries who claim them.

True that.  Maybe they'll use it to get the resources there.  If the GKR did claim these islands, now they have a territorial dispute with China and Taiwan.