There are some similarities, but it must be a different family. My family has always spelled our name with an 'e' at the end.My grandfather came from Italy as a teenager in 1916, with his mother and younger siblings. My grandmother, who was not a Dolce, (but of course married one), had a brother named Nicholas.
But my grandmother's family was from Bari. My grandmother was born in 1907. Her brother Nicholas was older, but only by a few years. So the Nicholas in my family was not an adult in 1908, and his children would not have the Dolce/Dolci name.None of the names you mention sound familiar on my Dolce side.
It seems that there are a few Dolce families out there. I've met a few other Dolces, and we weren't able to put together a family connection...at least, not yet.Maybe this will sound familiar to someone else out there!