Have you seen Joseph in the 1920 census? He is also listed as born in France abt 1862? I doubt that this Peter is their father as Andrew didn't come to America until 1895 and even though we know that Dominic did I find it unusual that Dominic's father would come with one son and leave another in France. Especially where Andrew is listed as a Chef so if he stayed it certainly wasn't for work reasons, he could take his work anywhere.
We have a ton of speculation on this family, we need to see if anything concrete can be found. I'm going to see if I can locate the death record for Dominic and start from there. Later cuz, Bob Birt