You're right, that may be a difficult story to find out about.
The death records in Italy do not usually give a cause of death. So Francesco's morti will only contain information on his age, his date, time and place of death, and the name of his wife if she survived him.
BTW - have located two possibilities for birth records for Maria Romana Crocco Gallo's mother - Antonia Maruca.
Checked the birth index from 1858-1878 and found these:
Antonia Maruca born 17 September 1863, to Giovanni Maruca, 36, day laborer, and to his wife Rose DeLuca, 32.
Antonia Maruca born 9 June 1875, to Gennaro, 43, day laborer, and to his wife Isabella Gallo, daughter of deceased Rosario.
There is a notation on this record, but it has been purposely blocked (funny, I found that on a lot of the record notations

)
Have been looking for the marriage record of Saverio Crocco and Antonia Maruca to help identify the correct record from above.
T.