I can corroborate that OSS wanted to go into VN. A relative was OSS during the war, the real part, not the Oh So Social part. OSS/CIA wanted him to continue with them after the war as they said they were going into Viet Nam. He declined the offer.
About Ho, I remember being completely blown away at the picture of him in formal morning attire at the Treaty of Versailles talks in 1919. They petitioned to become an independent state but were ignored. One wonders how history might have been different.
some consider an OSS officer, Dewey, the first American Casualty of the VN war.