Doubts regarding the post about the 1.5 billion KRW liquidation

https://mlbpark.donga.com/mp/b.php?m=search&p=31&b=bullpen&id=202608300118341384&select=spf&query=%EC%BD%94%252F%EC%A3%25BC%252F%EB%B6%80&shop=&subselect=&subquery=&user=&site=donga.com&reply=&source=&pos=&sig=h6j9GgtYhhXRKfX2hda9RY-1jhlq
In this post, the user claims they deposited funds because the customer center said 120% would be sufficient, but a forced liquidation (margin call liquidation) occurred.
Looking at the title "1.5 billion KRW liquidation," if we assume a 450 million KRW margin and a 1.05 billion KRW credit loan, then 120% of 1.05 billion KRW is 1.26 billion KRW. To meet this, they deposited 76 million KRW, which would make the total stock valuation 1.18 billion KRW. If they needed to meet 140%, that would be 1.47 billion KRW, meaning they would have had to deposit an additional 210 million KRW.
Also, according to the news, half of the forced liquidation happened on the 29th and the full liquidation occurred on the 30th. Even if they had fully met the 140% margin requirement, the stock price dropped by 8% on the 29th, meaning they would have had to deposit another 100 million KRW. They would have needed to inject a total of about 400 million KRW more.
I doubt whether they would have deposited an additional 400 million KRW on top of the original 450 million KRW. Furthermore, if they had 400 million KRW, they could have purchased stocks at a lower price on the 29th as the brokerage suggested—it would be fewer shares than what was sold, but they could have bought some—yet they didn't do that.
Additionally, they called the customer center on the 28th, and the forced liquidation occurred as soon as the market opened on the 29th. I wonder why they waited until the 30th to call. If the forced liquidation happened on the 29th, they should have called immediately to dispute it; calling on the 30th is also strange.
Regarding the full liquidation on the 30th, it seems difficult to hold the brokerage accountable. Looking only at the forced liquidation on the 29th, since the liquidation was executed at the opening price as the brokerage employee claimed, it was more profitable than the closing price, making it difficult to seek compensation. Also, they should remove "1.5 billion KRW liquidation" from the title, as the principal was 1.5 billion KRW, but the stock price at the time was much lower.