Short answer is that this is impossible as there were no US soldiers to speak of in Korea in June 1950.

Here is the timeline of events.

• August and September of 1945, Japan surrenders, ending the Pacific War. MacArthur and Co. sign the surrender documents in Tokyo on September 2, 1945.

• September 4th, elements of the XXIV Corps land at Kimpo Airfield, west of Seoul.

• September 8th, the first wave of XXIV Corps lands at Incheon (Jinsen in Japanese).

• September 9th, the commanding general for Japanese forces, Lt. Gen Kozuki, officially surrenders to Lt. General John Hodge, the commander for XXIV Corps.

• SIX MONTHS LATER, on March 15th, the 40th infantry division leaves Incheon for home.

Now, a corps contains upwards of 30,000 men and it's made up of two or more divisions. A division contains roughly 15,000 men, so when the 40th leaves Korea, assuming a full strength corps and division, we're talking HALF the US military strength in Korea. Since this was a corps that had seen combat on Okinawa and elsewhere, and the US military was demobilizing as fast as possible, the numbers were probably lower in reality.

On August 15, 1948, the Republic of Korea was established and the US Army Military Government in Korea (USAMGK) was shut down. The US Security Council had decided that they wanted the occupation to begin to end by December 31, 1948. In January of 1949, the USA 7th Division had moved to Hokkaido leaving Korea without US forces. A report was written detailing the concerns of having no forces in Korea. Ominously, it states that the North/communists would probably try to conquer the South, but that the South should be able to defend itself by January, 1950. The problem with this is that Syngman Rhee wanted to attack the North and re-unify, so the US didn't give him proper arms and his military suffered for it.

TLDR - there were only a handful of advisors in country when the war started. All occupation forces had been removed between March of 1946 and January of 1949.