I couldn't find a John Fitzgerald in the Dayton death index.... but found three in the Montgomery County index.... but the ages don't fit....
John Fitzgerald, died 3/22/1904, single, age 66, died at Natl Military Home, born New York, farmer, died of chronic cystitis
John Fitzgerald, died 1903 (no month or day shown), no age shown, died at Brookville, Ohio
John Fitzgerald, died 8/1/1905, single, age 70, died at St Elizabeth Hospital, born Ireland, laborer, residence at Middletown, Ohio
guess the middle one is most likely based on what you said before.... i honestly don't understand why there's so little info in this index entry.... this would indicate that the death record at the Reibold building would have no more info either....ordinarily, i'd think a record without an age was for an infant.... but pretty hard to tell