I am not sure the F5 are from Earth, but it is a likely place given they are associated with the Temple of Five, which was built by Earthlings.

There is no reason to conclude there was human-Cylon friendship in any given cycle, but it is true that the Final Five were not involved in the genocide of the colonies, and further that they appear to have been involved in Galactica and the fleet escaping it. Furthermore Tigh fought in the first cylon war.

The mystery of why the 7 Cylons know there are 5 others, though they have not seen them and are forbidden from curiousity or discussion about them remains unresolved. But it makes it likely the final 5, or somebody associated with them, had something to do with the programming of the 7.