Sorry unable to help with finding the grave, however, noted that you state a son was born in 1905 and refer to the "paternity index", not sure what you mean by this? If an Action for Declarator of Parentage was granted, there would be a Register of Corrected Entries (RCE) document attached to the original birth entry and would also be shown by an annotation stamped in the margin on the original birth entry. This is the only way that you would know whether a Decree was granted.
