One database shows: Pfc. Charles A. Oliver SN: 31308419 initial burial: Saint Juan Cemetery, Besanco, France final burial: private cemetery in MA
Another database of WW2 KIA's by county shows he was from Middlesex Co., MA
Unfortunately, there's no comprehensive listing of where the remains of WW2 KIA's were repatriated to.You might want to post a message to the Middlesex Co. GenForum on this site. There are also a number of Middlesex Co. genealogy sites that might help.
See message 10907 on this board.You might want to write for his Individual Deaceased Personnel File from Govt sources.That file will show where his remains were buried.