There doesn't seem to be any mention of his interment anywhere, nor is there any mention of him on an official U.S. Goverment War Memorial.

He isn't listed on the American Battle Monuments Commisssion site.

Nor is he listed on the Department of Veterans Affairs site.

It suggests to me that if his remains were repatriated to the United States they were probably re-interred at a cemetery near to his wife's place of residence, or else at a pre existing family plot.

I suggest that you contact the Department of Veterans Affairs.

http://www.abmc.gov/home.php

http://www.abmc.gov/search/wwi.php

http://www.va.gov/

http://gravelocator.cem.va.gov/