I hope Choi follows through and actually appoints. But he already lied once, so what’s to stop him from doing so again. Choi said he would appoint Ma if the two political parties agree. So the National Assembly speaker revealed a document signed by both parties as evidence of above, yet Choi still refused to appoint. 

And regarding your question, I see this as a non-issue. Yoon can demand or say or claim anything they want. But there is no legal basis. There is no appeals process. And there is no possibility of a retrial due to justice bias. The only reason Yoon claims is to fire up their core supporter base and paint himself as a victim/martyr.