Thanks for your research. I was totally unaware that there was a grave site for him at Grafton WV which was right down the road from my home in Fairmont. It still looks like he is MIA. He apparently is known to be KIA so maybe his dogtags got picked up or his death witnessed or whatever the procedure is but his body remains at Chosin. There may be nothing to recover.
I'm a few miles from the Army History Center in Carlisle, PA. They have quite a lot of information there but not official records. I spent a couple of days up there trying to find more information on the 31sts fight at the Chosin. There are personal letters, photos and stuff there at Carlisle and the unit was reconstituted but there wasn't much continuity. I wonder if any of the survivors were in good enough shape to form the nucleus of a new unit.
I hope you are able to find the people and answers you are seeking.