I think the trick would be to convince China that Nork nukez are a threat to them.
Possibly by reminding them of Gerber Baby’s threats towards them two years or so back.
It’d be hilarious to watch Gerber Baby get roflstomped by China.
FWIW: According to reports Chian has either 300,000 or 450,000 troops (mechanized plus artillery and missile batteries) moved up along the border and has been constructing what appear to be refuge camps in the same area. They have also said that any nuclear detonation which pushes fallout over China will be returned in kind. (Prevailing winds seem to be favorable to taking out the NOKO capital and a bit further north without the winds pushing fallout into China.)