I don’t see how President Yoon stays in power because this is clearly a hint from the PPP leader that they will join the opposition in impeachment if he doesn’t suspend his Presidential powers:

The leader of the ruling party said Friday that President Yoon Suk Yeol needs to be swiftly suspended from exercising power, revealing that Yoon ordered the arrests of prominent politicians during his aborted martial law declaration.
Han Dong-hoon of the People Power Party (PPP) said there is a possibility that the president may again take a “radical” action like the botched declaration of martial law if Yoon clings to the presidential power.
“Given the newly revealed facts, I believe it is necessary to promptly suspend President Yoon Suk Yeol from his duties to protect the Republic of Korea and its people,” Han told an emergency meeting of the party’s leadership at the National Assembly, referring to South Korea by its official name.
Han pointed out it was confirmed Thursday that Yoon had instructed Counterintelligence Commander Yeo In-hyung to detain key political figures, accusing them of being “anti-state” forces, and had even mobilized intelligence to detain them. (Yonhap)
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