As far as I know, the Chiementin shop in this case is located in Brendola in the province of Vicenza, not in Venice. The Chiementin shop has been around for a long time and if I am not mistaken have been responsible to build up the occasional show bike for Campagnolo over the years. As far as Galmozzi goes, you could always contact Angelo Galmozzi and ask him for more details. He is still alive and well in Milan (He only speaks Italian however). I am virtually certain that the frame has been repainted and fiddled with. The top tube braze-ons and the under the BB cable routing are not original.

PS: I hope that you got the bike for considerably less than what the scooter seller was asking for the bike...