I know this is an old thread so it may go un-answered now, but just a hint for you; Asmara wasn't in Ethiopia, it was in Eritrea, and that is where most of the Italians lived. My Mother was born in 1937 in Adi Ugri, Eritrea and then was raised in Asmara Eritrea. She lived there until 1961 where she then married my Father who was stationed there at Kagnew Station (U.S. Army communications post) so I wonder if she knew your Father as well? Her name was Elena Cunna; her father was Loiso Cunna.
After World War 2 the U.K and the U.N gave Eritrea to Ethiopia to "manage" the country (which is where the confusion comes from) but an immediate war that finally ended in the 1990s established Eritrea as an independent country. But even my Mother's birth certificate references as Eritrea, not Ethiopia... so hoping this helps with your search, and hope you do see this and hope to hear if your Father grew up with my Mother!