I replied above but heard nothing.I have since found much more info, so I thought I would take a shot in the dark and reply again.
First, a genealogy project for the Bertganolli family from Fondo (south end of Val di Non) is an invaluable source IF your ancestors come from the 6 villages.Yours do (as do mine).Here is their homepage: http://freepages.genealogy.rootsweb.ancestry.com/~bertagnolli/http://freepages.genealogy.rootsweb.ancestry.com/~bertagnolli/
It includes your grandfather and great grandfather, and more.See “Agosti, Pietro Isidoro (1867 - ) - male” on this page:
This is basically ALL of the records that can be found in the Mormon Family Heritage microfilm records for these areas.There are 1,067 Agosti’s on its various pages(!),including my grandfather Serafino Giovanni from Scanna di Livo on the same page as Pietro Isidoro.If you do find someone, you can trace back paternal and maternal lines.My paternal lines goes back 8 generations to 1682, but does not appear to meet yours in that time frame, thouh perhaps your great great grandmother’s Agosti line does.