Why was the investigation delayed despite rain being forecast in the landmine accident area?

◇ Military refused UN Command investigation once
While the ROK military maintains the position of conducting an on-site investigation after the Chuseok holiday, the UN Command, which holds overall authority including access control and management of the DMZ area, is reportedly supporting a prompt on-site investigation. A military official familiar with the internal affairs of the 1st Corps stated, “I understand that the UN Command attempted to conduct an on-site investigation yesterday (22nd), but it did not take place because the ROK military refused.”
https://n.news.naver.com/article/023/0004000229?sid=100
Military hesitates to ‘secure evidence of landmines,’ delaying on-site investigation until after Chuseok holiday
Military cites “trauma of soldiers” as reason, amid concerns over North Korean military potentially tampering with the site; regarding the landmine explosion that occurred near the Military Demarcation Line (MDL) in Paju, Gyeonggi Province on the 21st, the military stated they would “conduct an on-site investigation with the UN Command after the Chuseok holiday.”
n.news.naver.com