About the North Korea investors, no offense but are you sure that there are people that has access to the internet living there? Base on the documentary that I've watched, people are restricted to access to the web there.
You don't have budget for the extraction? you can manually check all of those KYC and just hire someone to work on it. Monitoring those investors that you are restricting base on their country.
Lol, it may sounds lime true about the North kor people but there are other things that OP consider esp. that US and north kor has no good relationship and has a tension because of maasive destruction weapon being held by north kor and ready for a war. Meaning to say that investors are not from the north kor people but the government of North kor itself to take advantage on the US trade.
I'm thinking that OP is wrong about the North Korea but it's the South Korean investors. OP can easily figure it out of stopping those investors that they don't like within their ICO premises. They only have to monitor and check those investors manually who will send and pass their KYC. That's what I'm telling him that he can do it on their own without any intervention of some systems that they have to avail and pay. Since they have no budget with that, manual process is the solution.