The German casualty lists are currently being databased, but at the moment most of the entries are from the early months of the war. Initially, the lists were ordered by unit, but that was discontinued after about a year, whereupon they alphabetical. Only after the war ended did the lists resume identifying the soldier's unit. If he was born in 1900 then he should have only seen service toward the very end, unless he lied about his age. It's possible that he will therefore appear in one of the post-war lists. It will be awhile before this database is complete, though.

http://java.genealogy.net/eingabe-verlustlisten/search